M.C.Q (1 Marks)

MCQ 11 Mark

For the given reaction:

$Image$

$P$ is

Answer

Correct option: A.

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MCQ 21 Mark

Given below are two statements:

Statement $I$ : The boiling point of three isomeric pentanes follows the order

n-pentane $>$ isopentane $>$ neopentane

Statement $II$ : When branching increases, the molecule attains a shape of sphere. This results in smaller surface area for contact, due to which the intermolecular forces between the spherical molecules are weak, thereby lowering the boiling point.

In the light of the above statements, choose the most appropriate answer from the options given below:

A
Both Statement $I$ and Statement $II$ are incorrect
B
Statement $I$ is correct but Statement $II$ is incorrect
C
Statement $I$ is incorrect but Statement $II$ is correct
✓
Both Statement $I$ and Statement $II$ are correct

Answer

Correct option: D.

Both Statement $I$ and Statement $II$ are correct

d
Both statement $I$ and statement $II$ are correct.

Boiling point of n-pentane $=309 \mathrm{~K} $

isopentane $=301 \mathrm{~K} $

neopentane $ =282.5$

As branching increases molecules attain the shape of a sphere results in smaller area of contact thus weak intermolecular forces between spherical molecules, which are overcome at relatively lower temperature. Leading to decrease in boiling point.

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MCQ 31 Mark

Weight $(g )$ of two moles of the organic compound, which is obtained by heating sodium ethanoate with sodium hydroxide in presence of calcium oxide is :

A
$18$
B
$16$
✓
$32$
D
$30$

Answer

Correct option: C.

$32$

c
This reaction is called soda lime decarboxylation

Molar mass of $CH _4=16\,g / mol$

Weight of 2 moles of $CH _4=16 \times 2$

$=32\,g$

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MCQ 41 Mark

Consider the following compounds/species:

The number of compounds/species which obey Huckel's rule is $..........$

A
$6$
✓
$4$
C
$5$
D
$2$

Answer

Correct option: B.

$4$

b
Huckle's rule $=(4 n+2) \pi$ electrons Comp $(i), (ii), (v), (vii)$ obey Huckle's rule.

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MCQ 51 Mark

Compound $X$ on reaction with $O _{3}$ followed by $Zn /$ $H _{2} O$ gives formaldehyde and $2-$methyl propanal as products. The compound $X$ is :

A
$2-$Methylbut$-1-$ene
B
$2-$Methylbut$-2-$ene
C
Pent$-2-$ene
✓
$3-$Methylbut$-1-$ene

Answer

Correct option: D.

$3-$Methylbut$-1-$ene

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MCQ 61 Mark

Which compound amongst the following is not an aromatic compound?

Answer

Correct option: C.

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MCQ 71 Mark

$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COO}^{-} \mathrm{Na}^{+} \xrightarrow[\mathrm{Heat}]{\mathrm{NaOH},+?} \mathrm{CH}_{3} \mathrm{CH}_{3}+ \mathrm{Na}_{2} \mathrm{CO}_{3} .$

Consider the above reaction and identify the missing reagent/chemical.

A
$\mathrm{B}_{2} \mathrm{H}_{6}$
B
Red Phosphorus
✓
$\mathrm{CaO}$
D
$DIBAL-H$

Answer

Correct option: C.

$\mathrm{CaO}$

c
$\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{COONa} \xrightarrow[\Delta]{\mathrm{NaOH}+?} \mathrm{CH}_{3}-\mathrm{CH}_{3}$

It's decarboxylation in presence of sodalime so missing reagent is $\mathrm{CaO} .$ $(\mathrm{NaOH}+\mathrm{CaO})$ sodalime

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MCQ 81 Mark

Which of the following is a free radical substitution reaction?

A
Propene with $HBr /\left( C _{6} H _{5} COO \right)_{2}$
B
Benzene with $Br _{2} / AlCl _{3}$
C
Acetylene with $HBr$
✓
Methane with $Br _{2} / hv$

Answer

Correct option: D.

Methane with $Br _{2} / hv$

d
Reaction of methane with $Br _{2}$ in the presence of light is a free radical substitution reaction.

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MCQ 91 Mark

An alkene on ozonolysis gives methanal as one of the product. Its structure is

Answer

Correct option: D.

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MCQ 101 Mark

Urea reacts with water to form $A$ which will decompose to form $B. B$ when passed through $Cu ^{2+}( aq ),$ deep blue colour solution $C$ is formed. What is the formula of $C$ from the following$?$

A
$CuCO _{3} \cdot Cu ( OH )_{2}$
B
$CuSO _{4}$
✓
$\left[ Cu \left( NH _{3}\right)_{4}\right]^{2+}$
D
$Cu ( OH )_{2}$

Answer

Correct option: C.

$\left[ Cu \left( NH _{3}\right)_{4}\right]^{2+}$

c
$NH _{2} CONH _{2}+ H _{2} O \rightarrow CO _{2}+ NH _{4} OH$

$(A)$

$NH _{4} OH \stackrel{\Delta}{\longrightarrow} NH _{3}+ H _{2} O$

$(B)$

$Cu ^{+2}( aq )+4 NH _{3} \rightarrow\left[ Cu \left( NH _{3}\right)_{4}\right]^{+2}($ deep blue $)$

$(C)$

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MCQ 111 Mark

Which of the following alkane cannot be made in good yield by Wurtz reaction$?$

A
n$-$Butane
B
n$-$Hexane
C
$2,3 -$Dimethylbutane
✓
n$-$Heptane

Answer

Correct option: D.

n$-$Heptane

d
n$-$Heptane can not be made in good yield using Wurtz reaction since it is unsymmetrical alkane.

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MCQ 121 Mark

The most suitable reagent for the following conversion is

A
$Na/lquid\; NH_{3}$
✓
$\mathrm{H}_{2}, \mathrm{Pd} / \mathrm{C},$ quinoline
C
$Zn/HCl$
D
$\mathrm{Hg}^{2+} / \mathrm{H}^{+}, \mathrm{H}_{2}O$

Answer

Correct option: B.

$\mathrm{H}_{2}, \mathrm{Pd} / \mathrm{C},$ quinoline

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MCQ 131 Mark

In the following reaction,

$\mathrm{C}\mathrm{H}_{3} -\mathrm{C} \equiv \mathrm{CH} \xrightarrow[873\;K]{\text { red hot iron tube}} \mathrm{A}$

the number of sigma$(\sigma)$ bonds present in the product $A$ is

✓
$21$
B
$9$
C
$24$
D
$18$

Answer

Correct option: A.

$21$

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MCQ 141 Mark

The alkane that gives only one mono-chloro product on chlorination with $Cl_2$ in presence of diffused sunlight is

A
$2,2-$dimethylbutane
✓
neopentane
C
$n-$pentane
D
Isopentane

Answer

Correct option: B.

neopentane

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MCQ 151 Mark

The number of sigma ( $\sigma$ ) and pi ( $\pi$ ) bonds in pent$- 2 -$en$- 4 -$yne is

✓
$10\sigma $ bonds and $3\pi$ bond
B
$8\sigma $ bonds and $5\pi$ bond
C
$11\sigma $ bonds and $2\pi$ bond
D
$13\sigma $ bonds and $\pi$ bond

Answer

Correct option: A.

$10\sigma $ bonds and $3\pi$ bond

a
$\begin{array}{*{20}{c}} {{\text{H}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ {{\text{H - C - C = C - C}} \equiv {\text{C - H}}} \\ {|\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\;\;\,\,\,\,\,\,\,\,\,\,} \\ {{\text{H}}\,\,\,\,\,\,{\text{H}}\,\,\,\,\,\,{\text{H}}\,\,\,\,\;\;\,\,\,\,\,\,\,\,\,\,\,\,\,} \end{array}$

Number of sigma bonds $=10$

Number of $\pi$ -bonds $=3$

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MCQ 161 Mark

Match the catalyst with the process

Catalyst	Process
$(i) \;\mathrm{Na}_{2} \mathrm{O}$	$(a)$ The oxidation of ethyne to ethanal
$(ii) \;\mathrm{TiCl}_{4}+ \mathrm{Al(CH_3)}_{3}$	$(b)$ Polymerisation of alkynes
$(iii)\;\mathrm{PdCl_2} $	$(c)$ Oxidation of $SO_2$ in the manufacture of $H_2SO_4$
$(iv)\;$Nickel complexes	$(d)$ Polymerisation of ethylene

Which of the following is the correct option ?

✓
$i-c, ii-d, iii-a, iv-b$
B
$i-a, ii-b, iii-c, iv-d$
C
$i-a, ii-c, iii-b, iv-d$
D
$i-c, ii-a, iii-d, iv-b$

Answer

Correct option: A.

$i-c, ii-d, iii-a, iv-b$

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MCQ 171 Mark

An alkene $A$ on reaction with $\mathrm{O}_{3}$ and $\mathrm{Zn}-\mathrm{H}_{2} \mathrm{O}$ gives propanone and ethanal in equimolar ratio. Addition of $HCl$ to alkene $A$ gives $B$ as the major product. The structure of product $B$ is:

A
$Cl - C{H_2} - C{H_2} - \begin{array}{*{20}{c}}
{C{H_3}} \\
{|\,\,\,\,\,} \\
{CH} \\
{|\,\,\,\,\,} \\
{C{H_3}}
\end{array}$
B
$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_2}Cl} \\
{\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3} - C{H_2} - CH - C{H_3}}
\end{array}$
✓
$C{H_3} - C{H_2} - \begin{array}{*{20}{c}}
{C{H_3}\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{Cl\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
D
$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{H_3}C} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3} - CH - CH} \\
{\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\;\;|} \\
{\,\,\,\,\,\,\,Cl\,\,\,\;{H_3}C}
\end{array}$

Answer

Correct option: C.

$C{H_3} - C{H_2} - \begin{array}{*{20}{c}}
{C{H_3}\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{Cl\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$

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MCQ 181 Mark

Hydrocarbon $(A)$ reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to gaseous hydrocarbon contalning less than four carbon atoms. $(\mathrm{A})$ is

A
$CH\equiv CH$
B
$CH_2= CH_2$
C
$CH_3-CH_3$
✓
$CH_4$

Answer

Correct option: D.

$CH_4$

d
$\mathrm{CH}_{4} \xrightarrow[hv]{Br_2}-\mathrm{CH}_{3}-\mathrm{Br} \xrightarrow[ether]{Na} \mathrm{CH}_{3}-\mathrm{CH}_{3}$

(less than four 'C)

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MCQ 191 Mark

With respect to the conformers of ethane, which of the following statements is true ?

A
Bond angle changes but bond length resame.
B
Both bond angle and bond length change.
✓
Both bond angle and bond length remain same.
D
Bond angle resame but bond length changes.

Answer

Correct option: C.

Both bond angle and bond length remain same.

c
In conformation bond angle and bond length remain same.

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MCQ 201 Mark

Predict the correct intermediate and product in the following reaction :

${H_3}C - C \equiv CH\,\xrightarrow[{HgS{O_4}}]{{{H_2}O,\,{H_2}S{O_4}}}\,\mathop {Intermediate}\limits_{(A)} \,$$ \to \,\mathop {\Pr oduct}\limits_{(B)} $

A
$A \,: \, \begin{array}{*{20}{c}}
{{H_3}C - C = C{H_2}} \\
| \\
{OH}
\end{array}$ $ B\,\, :\, \begin{array}{*{20}{c}}
{{H_3}C - C = C{H_2}} \\
| \\
{S{O_4}}
\end{array}$
B
$A\,\, :\,\begin{array}{*{20}{c}}
{{H_3}C - C - C{H_3}} \\
{|\,|} \\
O
\end{array}$ $B\,\,:\, H_3C-C=CH$
✓
$A \,: \, \begin{array}{*{20}{c}}
{{H_3}C - C = C{H_2}} \\
| \\
{OH}
\end{array}$ $B\,\, :\,\begin{array}{*{20}{c}}
{{H_3}C - C - C{H_3}} \\
{|\,|} \\
O
\end{array}$
D
$ A\,\, :\, \begin{array}{*{20}{c}}
{{H_3}C - C = C{H_2}} \\
| \\
{S{O_4}}
\end{array}$ $B\,\, :\,\begin{array}{*{20}{c}}
{{H_3}C - C - C{H_3}} \\
{|\,|} \\
O
\end{array}$

Answer

Correct option: C.

$A \,: \, \begin{array}{*{20}{c}}
{{H_3}C - C = C{H_2}} \\
| \\
{OH}
\end{array}$ $B\,\, :\,\begin{array}{*{20}{c}}
{{H_3}C - C - C{H_3}} \\
{|\,|} \\
O
\end{array}$

c
$C{{H}_{3}}-C\equiv CH\xrightarrow[HgS{{O}_{4}}]{{{H}_{2}}O.{{H}_{2}}S{{O}_{4}}}\begin{matrix}
C{{H}_{3}}-C=C{{H}_{2}} \\
|\,\, \\
\,\,\,OH \\
\end{matrix}$ $\xrightarrow{Tautomerism}\begin{matrix}
CH3-C-C{{H}_{3}} \\
|| \\
O \\
\end{matrix}$

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MCQ 211 Mark

Amongst the following compounds the one which is most easily sulphonated is

A
Benzene
B
Nitro benzene
✓
Toluene
D
Chlorobenzene

Answer

Correct option: C.

Toluene

c
ટોલ્યુઈન

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MCQ 221 Mark

Which one is the correct order of acidity ?

✓
$CH\equiv CH > CH_{3}-C\equiv CH$$ > CH_2=CH_2 > CH_{3}-CH_3$
B
$CH\equiv CH > CH_2=CH_2 $$> CH_{3}-C\equiv CH > CH_{3}-CH_3$
C
$CH_{3}-CH_3 > CH_2CH_2 $$> CH_{3}-C \equiv CH > CH \equiv CH$
D
$CH_2=CH_2 > CH_{3}-CH= CH_2 $$> CH_{3}-C \equiv CH > CH \equiv CH$

Answer

Correct option: A.

$CH\equiv CH > CH_{3}-C\equiv CH$$ > CH_2=CH_2 > CH_{3}-CH_3$

a
$\mathrm{CH} \equiv \mathrm{CH}>\mathrm{CH}_{3}-\mathrm{C} \equiv \mathrm{CH}>$$\mathrm{CH}_{2}=\mathrm{CH}_{2}>\mathrm{CH}_{3}-\mathrm{CH}_{3}$

acc. to EN and Inductive effect.

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MCQ 231 Mark

Which of the following compounds shall not produce propene by reaction with $HBr$ followed by elimination or direct only elimination reaction ?

A
B
$H_3C-CH_2-CH_2OH$
✓
$H_2C = C=O$
D
$H_3C-CH_2-CH_2Br$

Answer

Correct option: C.

$H_2C = C=O$

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MCQ 241 Mark

The compound that will react most readily with gaseous bromine has the formula

✓
$C_3H_6$
B
$C_2H_2$
C
$C_4H_{10}$
D
$C_2H_4$

Answer

Correct option: A.

$C_3H_6$

a
Propene is most reactive towards $B r_{2}$ (gaseous) than $C H_{2}=C H_{2}, H C=C H \&$ butane due to most electron density.

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MCQ 251 Mark

The pair of electrons in the given carbanion, $CH_3C \equiv C^-,$ is present in which of the following orbitals ?

A
$sp^2$
✓
$sp$
C
$2p$
D
$sp^3$

Answer

Correct option: B.

$sp$

b
$\mathrm{CH}_{3}-\stackrel{sp}{\mathrm{C}}\equiv \stackrel{sp}{\mathrm{C}^{-}}$

Thus, pair of electrons is present in sp-hybridised orbital.

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MCQ 261 Mark

Which of the following can be used as the halide component for Friedel-Crafts reaction ?

A
Chlorobenzene
B
Bromobenzene
C
Chloroethane
✓
Isopropyl chloride

Answer

Correct option: D.

Isopropyl chloride

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MCQ 271 Mark

In which of the following molecules, all atoms are coplanar ?

Answer

Correct option: A.

a
Biphenyl is coplanar as all $C-$atoms are sp $^{2}$ hybridised and its geometry is trigonal planar.

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MCQ 281 Mark

In pyrrole the electron density is maximum on

A
$2$ and $3$
B
$3$ and $4$
C
$2$ and $4$
✓
$2$ and $5$

Answer

Correct option: D.

$2$ and $5$

d
Pyrrole has highest electron density at $C_{2}$ and $C_{5}$ due to highest stability of protonated intermediate

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MCQ 291 Mark

The correct statement regarding the comparison of staggered and eclipsed conformations of ethane, is

A
the eclipsed conformation of ethane ismore stable than staggered conformation even though the eclipsed conformation has torsional strain
✓
the staggered conformation of ethane is more stable than eclipsed conformation, because staggered conformation has no torsional strain
C
the staggered conformation of ethane is less stable than eclipsed conformation, because staggered conformation has torsional strain
D
the eclipsed conformation of ethane is more stable than staggered conformation, because eclipsed conformation has notorsional strain.

Answer

Correct option: B.

the staggered conformation of ethane is more stable than eclipsed conformation, because staggered conformation has no torsional strain

b
Magnitude of torsional strain depends upon the angle of rotation about $\mathrm{C}-\mathrm{C}$ bond. Staggered form has the least torsional strain and the eclipsed form has the maximum torsional strain. So, the staggered conformation of ethane is more stable than the eclipsed conformation.

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MCQ 301 Mark

Consider the nitration of benzene using mixed conc. $H_2SO_4$ and $HNO_3. $ If a large amount of $KHSO_4$ is added to the mixture, the rate of nitration will be

A
unchanged
B
doubled
C
faster
✓
slower.

Answer

Correct option: D.

slower.

d
$\mathrm{H}_{2} \mathrm{SO}_{4}+\stackrel{\oplus}{\mathrm{H}} \longrightarrow \mathrm{NO}_{2}+\mathrm{H \stackrel{\ominus}{S}O}_{4}+\mathrm{H}_{2} \mathrm{O}$

$\mathrm{KHSO}_{4} \longrightarrow \mathrm{K}^{\oplus}+\mathrm{H\stackrel{\ominus}{S}O}_{4}$

Due to common ion effect backward reaction will take so the formation $\mathrm{NO}_{2}^{+}$ decrease so nitration process will become slower.

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MCQ 311 Mark

In the reaction

$H - C\, \equiv CH\,\xrightarrow[{(ii)\,C{H_3}C{H_2}Br}]{{(i)\,NaN{H_2}\,/\,liq.\,N{H_3}}}\,X$

$\xrightarrow[{(ii)\,C{H_3}C{H_2}Br}]{{(i)\,NaN{H_2}\,/\,liq.\,N{H_3}}}\,Y$

$X$ and $Y$ are

A
$X= {2-}$Butyne$,\, Y = {2-}$Hexyne
B
$X= 1-$Butyne$,\, Y = {2-}$Hexyne
✓
$X= 1-$Butyne$,\, Y = {3-}$Hexyne
D
$X= {2-}$Butyne$, \,Y = {3-}$Hexyne.

Answer

Correct option: C.

$X= 1-$Butyne$,\, Y = {3-}$Hexyne

c
$H-C\equiv C-H\xrightarrow[liq.\,N{{H}_{3}}]{Na\,N{{H}_{2}}/}HC\equiv C\,Na$ $\xrightarrow[-NaBr]{C{{H}_{3}}C{{H}_{2}}-Br}CH\equiv C-C{{H}_{2}}-C{{H}_{3}}$

$C{{H}_{3}}-C{{H}_{2}}-C\equiv CH\xrightarrow[liq.\,N{{H}_{3}}]{Na\,N{{H}_{2}}/}$ $C{{H}_{3}}-C{{H}_{2}}-C\equiv C\,Na\xrightarrow[-NaBr]{C{{H}_{3}}C{{H}_{2}}-Br}$ $\underset{3-Hexyne}{\mathop{C{{H}_{3}}-C{{H}_{2}}-C\equiv C-C{{H}_{2}}-C{{H}_{3}}}}\,$

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MCQ 321 Mark

In the given reaction, the product $P$ is

Answer

Correct option: C.

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MCQ 331 Mark

In the reaction with $HCl,$ an alkene reacts in accordance with the Markovnikov's rule to give a product $1-$chloro${-1}$ methylcyclohexane. The possible alkene is

A
B
✓
$(A)$ and $(B)$
D

Answer

Correct option: C.

$(A)$ and $(B)$

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MCQ 341 Mark

The oxidation of benzene by $V_2O_5$ in the presence of air produces and high tempreture

✓
maleic anhydride
B
benzoic acid
C
phenol
D
benzoic anhydride.

Answer

Correct option: A.

maleic anhydride

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MCQ 351 Mark

A single compound of the structure, is obtainable from ozonolysis of which of the following cyclic compounds?

Answer

Correct option: C.

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MCQ 361 Mark

Identify $Z$ in the sequence of reactions :

$CH_3 CH_2 CH=CH_2 \xrightarrow{{HBr/{H_2}{o_2}}}\,Y\,\xrightarrow{{{C_2}{H_5}ONa}}Z$

✓
$CH_{3}-(CH_2)_3 - O - CH_2CH_3$
B
$(CH_3)_2CH - O - CH_2CH_3$
C
$CH_3(CH_2)_4 - O - CH_3$
D
$CH_3CH_2 - CH(CH_3) - O - CH_2CH_3$

Answer

Correct option: A.

$CH_{3}-(CH_2)_3 - O - CH_2CH_3$

a
$C{{H}_{3}}C{{H}_{2}}CH=C{{H}_{2}}\xrightarrow[(peroxide\,or\,anti-Markovnikov's\,effect)]{HBr/{{H}_{2}}{{O}_{2}}}$ $\underset{(Y)}{\mathop{\underset{1-Bromobu\tan e}{\mathop{\begin{matrix}
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Br \\
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,| \\
C{{H}_{3}}C{{H}_{2}}-CH-C{{H}_{2}} \\
\,\,\,\,| \\
\,\,\,\,\,H \\
\end{matrix}}}\,}}\,\xrightarrow[\Delta ]{{{C}_{2}}{{H}_{5}}ONa}$ $\underset{(Z)}{\mathop{C{{H}_{3}}{{(C{{H}_{2}})}_{3}}-O-C{{H}_{2}}C{{H}_{3}}}}\,$

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MCQ 371 Mark

What products are formed when the following compound is treated with $Br_2$ in the presence of $FeBr_3$ ?

Answer

Correct option: C.

c
$-\mathrm{CH}_{3}$ group is o.p-directing. Because of crowding, no substitution occurs at the carbon atom between the two $-\mathrm{CH}_{3}$ groups in $\mathrm{m}$ -Xylene, even though two $-\mathrm{CH}_{3}$ groups activate that position.

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MCQ 381 Mark

Which of the following organic compounds has same hybridization as its combustion product $(CO_2)\,?$

A
Ethane
✓
Ethyne
C
Ethene
D
Ethanol

Answer

Correct option: B.

Ethyne

b
Hybridisation of carbon $=s p^{3-n u m b e r\;of\; \pi -bonds}$ $\ln C O_{2}, \begin{array}{l}{\left(O =C=O\right)} \\ { { \quad 1\pi } \;\;\;\;1 \pi }\end{array}$ hybridisation of carbon

$=s p^{3-2}=s p$

In ethyne or acetylene, $C_{2} H_{2},\left(H-C_{2 \pi}^{=} C-H\right)$

hybridisation of carbon $=s p^{3-2}=s p$

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MCQ 391 Mark

In the following reaction:

$HC \equiv CH\,\xrightarrow[{H{g^{2 + }}}]{{{H_2}S{O_4}}}\,'P'$

Product $'P'$ will not give

A
Tollen's reagent test
B
Brady's reagent test
✓
Victor Meyer test
D
Iodoform test

Answer

Correct option: C.

Victor Meyer test

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MCQ 401 Mark

Which of the following compounds will not undergo Friedal-Craft's reaction easily?

✓
Nitrobenzene
B
Toluene
C
Cumene
D
Xylene

Answer

Correct option: A.

Nitrobenzene

a
Friedal Craft reaction fails when strong deactivating group is attached with benzene ring.

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MCQ 411 Mark

Which of the following chemical system is non aromatic ?

Answer

Correct option: D.

d
The molecules which do not satisfy Huckel rule or $(4 n+2) \pi$ -electron rule are said to be nonaromatic. The compound (d) has total $4 \pi e^-$. It does not follow $(4n + 2)$ rule. So it is non-aromatic compound. All other compounds $(a, b, c)$ are planar and have $6 \pi e^{-},$ so they are aromatic.

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MCQ 421 Mark

Some $meta-$ directing substituents in aromatic substitution are given. Which one is most deactivating?

A
$- COOH$
✓
$- NO_2$
C
$- C\equiv N$
D
$- SO_3H$

Answer

Correct option: B.

$- NO_2$

b
$-\mathrm{NO}_{2}$ is most deactivating due to - $\mathrm{I}$ and $-\mathrm{M}$ effect.

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MCQ 431 Mark

Which of the following shows only one brominated compound

A
Butene $-2$
✓
$2, 2-$ dimethylpropane
C
Butyne $-1$
D
Butanol $-3$

Answer

Correct option: B.

$2, 2-$ dimethylpropane

b
Option $A$ will give $2$ mono brominated products, as $Br$ can go on $C _1 / C _2$.

Option $B$ will give $1$ mono brominated products, as $Br$ can go on $C _1$.

Option $C$ will give $1$ mono brominated products, as $Br$ can go on $C _1 / C _2 / C _3 / C _4$.

Option $D$ will give $2$ mono brominated products, as $Br$ can go on $C _1 / C _2 / C _3 / C _4$.

Therefore,Option $B$ is correct answer for this question.

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MCQ 441 Mark

Kerosene is used as fuel because it is

A
Less volatile
✓
More volatile
C
Cheap
D
Abundantly available

Answer

Correct option: B.

More volatile

b
It’s obvious.

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MCQ 451 Mark

$C{H_3} - C{H_2} - C{H_2} - C{H_3}\mathop {}\limits_{} {\rm{}}$ $ \xrightarrow[HBr]{AlCl_3} $ Product in above reaction is

A
$\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_2} - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
✓
$C{H_3} - \mathop {\mathop {CH}\limits_{|\,\,\,\,\,\,} }\limits_{C{H_3}} - C{H_3}$
C
$\mathop {\mathop {C{H_2}}\limits_{\,\,|\,\,\,\,\,\,\,\,\,\,} }\limits_{Br\,\,\,\,} - C{H_2} - \mathop {\mathop {C{H_2}}\limits_{|\,\,\,\,\,\,\,\,} }\limits_{C{H_3}} $
D
All of these

Answer

Correct option: B.

$C{H_3} - \mathop {\mathop {CH}\limits_{|\,\,\,\,\,\,} }\limits_{C{H_3}} - C{H_3}$

b
$C{H_3} - C{H_2} - C{H_2} - C{H_3}\mathop {}\limits_{} {\rm{}}$ $ \xrightarrow[HBr]{AlCl_3} C{H_3} - \mathop {\mathop {CH}\limits_{|\,\,\,\,\,\,} }\limits_{C{H_3}} - C{H_3}$

When $n$-butane is heated in the presence of $AlCl _{3} / HBr$.

It will be converted into Iso-butane.

It is a rearrangement reaction.

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MCQ 461 Mark

The chemical added to leaded petrol to prevent the deposition of lead in the combustion chamber is

A
Iso-octane
✓
Ethylene dibromide
C
Tetraethyl lead
D
Mercaptan $ (e)n-$Heptane

Answer

Correct option: B.

Ethylene dibromide

b
It’s obvious.

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MCQ 471 Mark

Which of the following has the highest boiling point

A
Neopentane
B
$n-$ butane
✓
$n-$ heptane
D
Isobutane

Answer

Correct option: C.

$n-$ heptane

c
The boiling point of $n$-heptane is $98.42$ degrees celsius.

The boiling point of $n$-butane is $-1$ degrees celsius.

The boiling point of neopentane is $9.5$ degrees celsius.

The boiling point of isobutane is $-11.7$ degrees celsius.

So $n$-heptane has the highest boiling point.

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MCQ 481 Mark

Which of the following does not react with $PC{l_5}$

A
$C{H_3}OH$
B
$C{H_3}COOH$
C
$C{H_3}CHO$
✓
${C_2}{H_6}$

Answer

Correct option: D.

${C_2}{H_6}$

d
$PCl _5$ usually used to replace - $OH$ group or oxygen of carbonyl group.

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MCQ 491 Mark

A reaction between methyl magnesium bromide and ethyl alcohol gives

✓
Methane
B
Ethane
C
Propane
D
Butane

Answer

Correct option: A.

Methane

a
(a)

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MCQ 501 Mark

Methane and ethane both can be obtained in single step from

✓
$C{H_3}I$
B
${C_2}{H_5}I$
C
$C{H_3}OH$
D
${C_2}{H_5}OH$

Answer

Correct option: A.

$C{H_3}I$

a
(a)$C{H_3}I + 2H \xrightarrow{Zn/HCl} C{H_4} + HI$

$C{H_3}I + 2Na + IC{H_3}\mathop {}\limits_{{\rm{}}} \xrightarrow[Ether]{Dry} C{H_3} - C{H_3} + 2NaI$

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MCQ 511 Mark

Petroleum consists mainly of

✓
Aliphatic hydrocarbons
B
Aromatic hydrocarbons
C
Aliphatic alcohols
D
None of these

Answer

Correct option: A.

Aliphatic hydrocarbons

a
Liquefied Petroleum Gas or LPG (also called Autogas) consists mainly of Aliphatic hydrocarbons

(propane, propylene, butane, and butylene in various mixtures).

It is produced as a by-product of natural gas processing and petroleum refining.

Petroleum is a mixture of a very large number of different hydrocarbons; the most commonly found molecules are alkanes (paraffins), cycloalkanes (naphthenes), aromatic hydrocarbons, or more complicated chemicals like asphaltenes.

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MCQ 521 Mark

The correct order of reactivity of $I, II$ & $III$ towards addition reactions is

A
$I > III > II$
✓
$I > II > III$
C
$III > II > I$
D
$III > I > II$

Answer

Correct option: B.

$I > II > III$

b
$(b)$ Cyclopropane is most unstable therefore more reactive toward addition reaction. Cyclopentene is most stable $\therefore$ less reactive .

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MCQ 531 Mark

Which of the following reactants is suitable for preparation of methane and ethane by using one step only ?

A
$H_2C = CH_2$
B
$CH_3OH$
✓
$CH_3 - Br$
D
$CH_3 - CH_2 - OH$

Answer

Correct option: C.

$CH_3 - Br$

c
$C{H_3} - Br\xrightarrow{{reduction}}C{H_4}$

$C{H_3} - Br\xrightarrow{{Wurtz}}C{H_3} - C{H_3}$

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MCQ 541 Mark

Product $(C)$ is

(figure) $\xrightarrow[CC{{l}_{4}}]{B{{r}_{2}}}(A)\xrightarrow[(ii)\,NaN{{H}_{2}}]{(i)\,alc.\,KOH}(B)\xrightarrow[(ii)\,C{{H}_{3}}-Cl]{(i)\,NaN{{H}_{2}}}(C)$

A
$Ph - C \equiv CNa$
B
$Ph - CH_2 -C \equiv CH$
✓
$Ph -C \equiv C - CH_3$
D
$Ph - CH = C =CH_2$

Answer

Correct option: C.

$Ph -C \equiv C - CH_3$

c
$\begin{array}{*{20}{c}}
{(A)\,Ph - CH - C{H_2} - Br}\\
{|\,\,\,\,\,\,\,\,\,\,}\\
{Br\,\,\,\,\,\,\,\,\,}
\end{array}\,\,\,\,\,\,(B)\,Ph - C \equiv C - H\,\,\,\,(C)\,\,Ph - C \equiv C - C{H_3}$

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MCQ 551 Mark

How many carbon atoms does an alkane (not a cycloalkane) need before it is capable to exist in enantiomeric form ?

A
$4$
B
$5$
C
$6$
✓
$7$

Answer

Correct option: D.

$7$

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MCQ 561 Mark

Among the following free radical bromination reactions, select those in which $2^o$ halide is the major product

A
$P, Q, R, S$
✓
$P, R, U$
C
$P, R, S, T$
D
$P, Q, R, S, T$

Answer

Correct option: B.

$P, R, U$

b
$(b)$ Bromine is more selective $\therefore$ it will form $3^o$ halide if there is presence of $3^o$ hydrogen. $\therefore\, Q, S, T,$ form $3^o$ halide as major and $P, R, U$ form $2^o$ halide as major.

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MCQ 571 Mark

$(A) + C{l_2}\xrightarrow{{hv}}$ monochloro product
To maximise the yield of monochloro product in the above reaction ?

A
$Cl_2$ must be added in excess
✓
Reactant $(A)$ must be added in excess
C
Reaction must be carried out in dark
D
Reaction must be carried out with equimolar mixture of $Cl_2$ and $A$

Answer

Correct option: B.

Reactant $(A)$ must be added in excess

b
$(b)$ If reactant $(A)$ is added in excess then maximum collission between $(A)$ and $C{l^ \bullet }$ in the rate determining step.

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MCQ 581 Mark

$C{H_3} - C{H_2} - C{H_2} - C{H_3}\xrightarrow{{B{r_2}/hv}}$

Major product in the above reaction is

✓
Racemic mixture
B
Meso
C
Diastereomers
D
Constitutional isomers

Answer

Correct option: A.

Racemic mixture

a
$(a)$ $2^o$ halide is major, due to formation of $sp^2$ -hybridized free radical racemization take place.

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MCQ 591 Mark

Product $(A)$ is

Answer

Correct option: B.

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MCQ 601 Mark

Homologue have different

A
General formula
B
Functional group
✓
Boiling point
D
Type of atoms

Answer

Correct option: C.

Boiling point

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MCQ 611 Mark

The reaction conditions leading to the best yields of $C_2H_5Cl$ are

✓
${C_2}{H_6}(excess)\, + \,C{l_2}\,\xrightarrow{{UV}}$
B
${C_2}{H_6}\, + \,C{l_2}\,\xrightarrow[{room\,\,\,temp.}]{{dark}}$
C
${C_2}{H_6}\, + \,C{l_2}(excess)\,\xrightarrow{{UV}}$
D
${C_2}{H_6}\, + \,C{l_2}\,\xrightarrow{{UV}}$

Answer

Correct option: A.

${C_2}{H_6}(excess)\, + \,C{l_2}\,\xrightarrow{{UV}}$

a
There can be polyhalogenation in this reaction but if excess of ethane is taken, then $C_5H_5Cl$ is obtained is major amount

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MCQ 621 Mark

$(CH_3)_2CHBr$ $\xrightarrow[{(2)\,CuI}]{{(1)\,Li}}\left( A \right)\xrightarrow{{{{\left( {C{H_3}} \right)}_2}CHC{H_2}Br}}B$

$'B'$ is

A
$(CH_3)_2CHCH_2CH_3$
B
$CH_3)_2CHCH(CH_3)_2$
✓
$(CH_3)_2CHCH_2CH(CH_3)_2$
D
$(CH_3)_2CHCH_2CH_2CH(CH_3)_2$

Answer

Correct option: C.

$(CH_3)_2CHCH_2CH(CH_3)_2$

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MCQ 631 Mark

$n-$ heptane $\xrightarrow[{600\,{}^oC}]{{C{r_2}{O_3}/{V_2}{O_3}}}$ ?

Answer

Correct option: B.

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MCQ 641 Mark

Arrange following alkanes in order of their boiling points

$(A)$ Pentane

$(B)\,2-$ Methyl butane

$(C)\,2,2-$ Dimethyl propane

✓
$A > B > C$
B
$A > C > B$
C
$C > B > A$
D
$C > A > B$

Answer

Correct option: A.

$A > B > C$

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MCQ 651 Mark

Choose the chain terminating step

(1)${H_2} \to {H^ \bullet } + {H^ \bullet }$

(2)$B{r_2} \to B{r^ \bullet } + B{r^ \bullet }$

(3)$B{r^ \bullet } + HBr \to {H^ \bullet } + B{r_2}$

(4)${H^ \bullet } + B{r_2} \to HBr + B{r^ \bullet }$

(5)$B{r^ \bullet } + B{r^ \bullet } \to B{r_2}$

A
$1$
B
$3$
C
$4$
✓
$5$

Answer

Correct option: D.

$5$

d
Step $5$ is chain termination step since no more radical formation is taking place.

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MCQ 661 Mark

Ethylene reacts with bromine to form

A
$Br - C{H_2} - C{H_3}$
B
$C{H_3} - CB{r_3}$
✓
$Br - C{H_2} - C{H_2}Br$
D
$CHB{r_3}$

Answer

Correct option: C.

$Br - C{H_2} - C{H_2}Br$

c
Alkenes react in the cold with pure liquid bromine, or with a solution of bromine in an organic solvent like tetrachloromethane. The double bond breaks, and a bromine atom becomes attached to each carbon.... In the case of the reaction with ethene, $1,2$-dibromoethane is formed.

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MCQ 671 Mark

Which of the following will give a mixture of cis and trans- $1,4$ -dimethyl cyclohexane, when undergo catalytic hydrogenation ?

A
B
C
✓
both $(a)$ & $(b)$

Answer

Correct option: D.

both $(a)$ & $(b)$

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MCQ 681 Mark

An optically active compound $A$ with molecular formula $C_8H_{14}$ undergoes catalytic hydrogenation to give mesa compound, the structure of $(A)$ is

Answer

Correct option: B.

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MCQ 691 Mark

Sodium ethoxide is a specific reagent for

A
Dehydration
B
Dehydrogenation
✓
Dehydrohalogenation
D
Dehalogenation

Answer

Correct option: C.

Dehydrohalogenation

c
(c) $C{H_3} - C{H_2} - C{H_2} - Br\mathop {}\limits_{{\rm{}}} $ $ \xrightarrow[C_2H_5ONa]{Dehydro halogenati on } $ $C{H_3} - CH = C{H_2} + HBr$

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MCQ 701 Mark

Which of the following has highest knocking

A
Olefins
B
Branched chain olefins
✓
Straight chain olefins
D
Aromatic hydrocarbons

Answer

Correct option: C.

Straight chain olefins

c
(c) Straight chain olefins has highest knocking.

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MCQ 711 Mark

Addition of bromine to $1, 3-$butadiene gives

A
$1, 2 $ addition product only
B
$1, 4$ addition product only
✓
Both $1, 2$ and $1, 4$ addition products
D
No reaction

Answer

Correct option: C.

Both $1, 2$ and $1, 4$ addition products

c
$1,3$-butadiene accompanies the bromine molecule to form two products.

They are $1,2$-add products and $1,4$-surplus products.

At low temperatures, the $1,2$-pair is predominant but at higher temperatures, the $1,4$-pair is predominant. Products $A$ and $B$ will be on this basis.

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MCQ 721 Mark

How can ethene be produced from ethanol

A
By dehydrohalogenation
B
By dehydrogenation
✓
By dehydration with conc. ${H_2}S{O_4}$ at ${170\,^o}C$
D
By reduction with hydrogen iodide

Answer

Correct option: C.

By dehydration with conc. ${H_2}S{O_4}$ at ${170\,^o}C$

c
When ethanol is heated in presence of conc. $H _2 SO _4$, dehydration takes place to give ethylene.

The reaction of ethene with steam to form ethanol can be reversed. This allows ethanol to be converted into ethene. This is called a dehydration reaction.

$\underset{Ethanol}{C _2 H _5 OH} \xrightarrow[160^{\circ}-170^{\circ} C]{Conc. H _2 SO _4} \underset{Ethene}{CH _2= CH _2}+ \underset{Water}{H _2 O}$

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MCQ 731 Mark

Isopropyl alcohol is obtained by reacting which of the following alkenes with conc. ${H_2}S{O_4}$ and ${H_2}O$

A
Ethylene
✓
Propylene
C
$2-$methyl propene
D
Isoprene

Answer

Correct option: B.

Propylene

b
(b) $\mathop {C{H_3} - CH = C{H_2}}\limits_{} + {H_2}O \xrightarrow[Markownikoff's \,rule]{Conc.H_2 SO_4} \mathop {}\limits_{{\rm{}}} \mathop {C{H_3} - \mathop {CH}\limits_{\mathop {|\,\,\,\,\,}\limits_{OH} } - C{H_3}}\limits_{{\rm{Isopropyl}}\,{\rm{\,alcohol}}} $

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MCQ 741 Mark

When 2-bromobutane reacts with alcoholic $KOH$, the reaction is called

A
Halogenation
B
Hydrogenation
C
Chlorination
✓
Dehydro-halogenation

Answer

Correct option: D.

Dehydro-halogenation

d
(d) $C{H_3} - \mathop {CH}\limits_{\mathop {|\,\,\,\,}\limits_{Br\,} } - C{H_2} - C{H_3} \xrightarrow{alc.KOH} \mathop {C{H_3}CH = CHC{H_3}}\limits_{{\rm{2 - butene}}} $
The reaction is dehydrohalogenation.

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MCQ 751 Mark

$1, 3-$butadiene reacts with ethylene to form

A
Benzene
B
Cyclohexane
✓
Cyclohexene
D
$2, 3$ dimethyl butane

Answer

Correct option: C.

Cyclohexene

c
the addition of ethene to $1,3$-butadiene to give cyclohexene.

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MCQ 761 Mark

Ethylene reacts with ozone gas to form the compound

✓
$HCHO$
B
${C_2}{H_5}OH$
C
D
$C{H_3}CHO$

Answer

Correct option: A.

$HCHO$

a
(a)

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MCQ 771 Mark

A mixture of $1-$chloropropane and $2-$chloropropane when treated with alcoholic $KOH$ gives

✓
$1-$propene
B
$2-$propene
C
Isopropylene
D
All the three

Answer

Correct option: A.

$1-$propene

a
(a) $C{H_3}C{H_2}C{H_2}Cl + KOH \to $$C{H_3} - CH = C{H_2} + KCl + {H_2}O$

$\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_3}} \\
{|\,\,\,\,\,} \\
{\,Cl\,\,\,\,}
\end{array}$ ${ + KOH \to C{H_3} - CH = C{H_2} + KCl + {H_2}O}$

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MCQ 781 Mark

The compound formed by passing ethylene gas into cold alkaline solution of $KMn{O_4}$ is

A
Ethyl alcohol
B
Acetaldehyde
C
Acetic acid
✓
Ethylene glycol

Answer

Correct option: D.

Ethylene glycol

d
(d) $\mathop {C{H_2} = C{H_2}}\limits_{{\rm{Ethene}}} \xrightarrow{Cold.\,alk \,KMnO_4} \mathop {\mathop {\mathop {C{H_2}}\limits_{|\,\,\,\,\,\,} }\limits_{OH} - \mathop {\mathop {C{H_2}}\limits_{|\,\,\,\,\,\,\,} }\limits_{OH\,} }\limits_{{\rm{Ethylene}}\,{\rm{glycol}}} $

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MCQ 791 Mark

When ethene is heated at ${400\,^o}C$ under high pressure, the product is/are

A
Carbon and ${H_2}$
✓
Polyethylene
C
Acetylene and ${H_2}$
D
None of these

Answer

Correct option: B.

Polyethylene

b
(b) $\mathop {n\,(C{H_2} = C{H_2})}\limits_{{\rm{(ethylene)}}} \xrightarrow[highpressure]{400\,^oC} \mathop {}\limits_{{\rm{}}} \,\,\mathop {{{( - C{H_2} - C{H_2} - )}_n}}\limits_{{\rm{(polyethylene)}}} $

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MCQ 801 Mark

Which decolorize aqueous bromine and gives white fumes of $HCl$ on reaction with $PC{l_5}$

A
$C{H_3}COC{H_2}CH = C{H_2}$
B
$C{H_3}C{H_2}C{H_2}C{H_2}C{H_3}$
✓
$C{H_3}CH = CHC{H_2}C{H_2}OH$
D
$C{H_3}OC{H_2}C{H_2}C{H_2}C{H_2}OH$

Answer

Correct option: C.

$C{H_3}CH = CHC{H_2}C{H_2}OH$

c
$CH _3- CH = CH - CH _2- CH _2- OH + PCl _5 \rightarrow K _3 C - CH = CH - CH _2-CH _2- Cl + MCl + POCl _3$

$\downarrow Br _2 \mid H _2 O$

Colour decolorises due to the presence of double bond.

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MCQ 811 Mark

What product is formed when $1-$chlorobutane react with alcoholic $KOH$

✓
$1-$butene
B
$2-$butene
C
$1-$butanol
D
$2-$butanol

Answer

Correct option: A.

$1-$butene

a
(a) $ClC{H_2} - C{H_2} - C{H_2} - C{H_3}$ $\xrightarrow{alc.KOH}$ $\mathop {C{H_2} = CH - C{H_2} - C{H_3}}\limits_{{\rm{1}} - {\rm{butene}}} $

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MCQ 821 Mark

The olefin which on ozonolysis gives $C{H_3}C{H_2}CHO$ and $C{H_3}CHO$ is

A
$1-$butene
B
$2-$butene
C
$1-$pentene
✓
$2-$pentene

Answer

Correct option: D.

$2-$pentene

d
(d) $C{H_3}C{H_2}CH = CHC{H_3} \xrightarrow[Zn/H_2O]{O_3} \mathop {}\limits_{} \mathop {C{H_3}C{H_2}CHO}\limits_{{\rm{Propanal}}} + \mathop {CHOC{H_3}}\limits_{{\rm{Ethanal}}} $

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MCQ 831 Mark

Bond length between carbon-carbon in ethylene molecule is......$ \mathop A\limits^o $

A
$1.54$
✓
$1.35$
C
$1.19$
D
$2.4$

Answer

Correct option: B.

$1.35$

b
A typical carbon-carbon single bond has a length of $154\, pm$, while a typical double bond and triple bond are $134\, pm$ and $120\, pm$, respectively.

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MCQ 841 Mark

When ethene reacts with bromine, it forms

A
Chloroethane
✓
Ethylene dibromide
C
$1 $ bromopropane
D
$1,2-$dichloroethene

Answer

Correct option: B.

Ethylene dibromide

b
The bromine loses its original red-brown colour to give a colourless liquid. In the case of the reaction with ethene,

$1,2$-dibromoethane is formed,also know as ethylene dibromide. This decolourisation of bromine is often used as a test for a carbon-carbon double bond.

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MCQ 851 Mark

Paraffins are soluble in

A
Distilled water
✓
Benzene
C
Methanol
D
Sea water

Answer

Correct option: B.

Benzene

b
(b)Paraffins or alkanes are non-polar compounds. Hence soluble in benzene.

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MCQ 861 Mark

Addition of $HCl$ to propene in presence of peroxides gives

A
$1-$Chloropropane
✓
$2-$Chloropropane
C
$3-$Chloropropane
D
Propene dichloride

Answer

Correct option: B.

$2-$Chloropropane

b
(b) $C{H_3} - CH = C{H_2} + HCl \xrightarrow{peroxide} \begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_3}} \\
| \\
{\,\,\,Cl}
\end{array}$

Peroxide rule is applicable only to $HBr$.

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MCQ 871 Mark

The name of the product obtained by the addition of $HI$ to propene in presence of peroxide catalyst is

A
Isopropyl iodide
B
$2-$Iodopropane
C
$3-$Iodopropane
✓
$1-$Iodopropane

Answer

Correct option: D.

$1-$Iodopropane

d
$C H_{3}-C H=C H_{2}+H I \stackrel{\text { Peroxide }}{\longrightarrow} C H_{3}-C H_{2}-C H_{2} I$

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MCQ 881 Mark

In the reaction ${C_2}{H_5}CH = C{H_2} + H - X \to $ Product. What is the product

A
${C_2}{H_5} - C{H_3}$
B
${C_2}{H_5}C{H_2} - C{H_2}X$
✓
${C_2}{H_5} - CHX - C{H_3}$
D
$C{H_3} - C{H_2}X - CH = C{H_2}$

Answer

Correct option: C.

${C_2}{H_5} - CHX - C{H_3}$

c
$C _2 H _5 CH = CH _2+ H - X \rightarrow C _2 H _5- CHX - CH _3$

When halide react with $1$ butene then tere will be a two product is possible.

$1.$ $C _2 H _5- CHX - CH _3$

$2.$ $C _2 H _5- CH _2- CHX_3$

But $90\, \%$ of the product is $C _2 H _5- CHX - CH _3$

And $10\, \%$ is $C _2 H _5- CH _2- CHX_3$.

Therefore our answer is Option $C$.

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MCQ 891 Mark

Alkene can be prepared from alkyl halide by the following reagent $R - X + N{u^ - } \to {\rm{Alkene}} + NuH$

✓
Alc. $KOH$ + heat
B
Aq. $KOH $ + cold water
C
$NaOH$
D
$LiOH$

Answer

Correct option: A.

Alc. $KOH$ + heat

a
When heated with strong bases, alkyl halides typically undergo a $1,2$-elimination reactions to generate alkenes. Typical bases are $KOH$ in the alcohol as solvent.

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MCQ 901 Mark

$2-$chlorobutane is heated with alcoholic $NaOH$, the product formed in larger amount is

A
$1-$Butene
B
$1-$Butyne
✓
$2-$Butene
D
All of these

Answer

Correct option: C.

$2-$Butene

c
(c) $C{H_3} - \mathop {CH}\limits_{\mathop {|\,\,\,\,\,}\limits_{H\,\,\,} } - \mathop {CH}\limits_{\mathop {|\,\,\,\,}\limits_{Cl\,\,} } - \mathop {C{H_2}}\limits_{\mathop {|\,\,\,\,\,\,\,\,}\limits_{H\,\,\,\,\,} } \mathop {} $ $\xrightarrow[alc.NaOH] {-HCL} $ $C{H_3}CH = CH - C{H_3}$

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MCQ 911 Mark

Ethylene has high b.p. and high vapour pressure at ${100\,^o}C$ and does not dissolve in water. Hence ethylene is separated by this method

A
Simple distillation
B
Vacuum distillation
✓
Vapour distillation
D
Alkali treatment

Answer

Correct option: C.

Vapour distillation

c
Steam Distillation also know as vapour Distillation:- This technique is used for separating substances which are immiscible with water, volatile in steam and having high vapour pressure at the boiling temperature of water. It is also used for purifying liquids which decompose at their normal boiling points.

Therefore, Ethylene has high $b.p.$ and high vapour pressure at $100^{\circ} C$ and does not dissolve in water. Hence, ethylene is separated by thi vapour distillation method.

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MCQ 921 Mark

The compound most likely to decolourize a solution of potassium permanganate is

A
$C{H_3}C{H_3}$
B
✓
$C{H_3}CH = CHC{H_2}C{H_3}$
D
$\mathop {\mathop {\mathop {\mathop {C{H_3} - C - C{H_3}}\limits^| }\limits^{\,\,\,\,\,\,C{H_3}} }\limits_| }\limits_{\,\,\,\,\,C{H_3}} $

Answer

Correct option: C.

$C{H_3}CH = CHC{H_2}C{H_3}$

c
(c)$C{H_3} - CH = CH - C{H_2} - C{H_3}$ it decolourizes $KMn{O_4}$ solution because double bond is present.

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MCQ 931 Mark

The product of reaction between propene and $HBr$ in the presence of a peroxide is

✓
$C{H_3} - C{H_2} - C{H_2}Br$
B
$C{H_3} - CHBr - C{H_3}$
C
$C{H_3} - C{H_2}Br$
D
$C{H_3} - CH = CHBr$

Answer

Correct option: A.

$C{H_3} - C{H_2} - C{H_2}Br$

a
(a) $C{H_3} - CH = C{H_2} + \mathop {HBr}\limits^{\,\,\,} \xrightarrow{peroxide} C{H_3} - C{H_2} - C{H_2} - Br$

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MCQ 941 Mark

Position of double bond in an organic compound is determined by

✓
Ozonolysis
B
Oxidation
C
Reduction
D
Hydrogenation

Answer

Correct option: A.

Ozonolysis

a
(a) Ozonolysis is useful in locating the position of a double bond in an alkene. The double bond is obtained by joining the carbon atoms of the two carbonyl compounds. For example

Let the product of ozonolysis be two molecules of ethanal.

$\mathop {C{H_3} - \mathop C\limits^{\mathop |\limits^H } = O}\limits_{} + O = \mathop C\limits^{\mathop |\limits^H } - C{H_3} \to $$\mathop {C{H_3} - CH = CH - C{H_3}}\limits_{{\rm{2}} - {\rm{Butene}}} $

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MCQ 951 Mark

A gas decolourises Bayer's reagent but does not react with Tollen's reagent, this gas is

✓
Ethene
B
Ethyne
C
Ethane
D
Methane

Answer

Correct option: A.

Ethene

a
The correct answer is - Ethene $\left( C _2 H _4\right)$ gas. Also, But-$1$-yne and But-$2$-yne are known for the same reactions.

Ammonical silver nitrate solution is also known as Tollen's reagent in chemical reaction studies.

These gases are known to decolourize aqueous bromine water. They also form a white precipitate when they react with aqueous ammoniacal silver nitrate solution.

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MCQ 961 Mark

The molecular formula of the first member of the family of alkenynes and its name is given by the set

A
$C_3H_2,$ alkene
B
$C_5H_6,\, 1-$ penten$-3-$yne
C
$C_6H_8, \,1-$hexen$-5-$yne
✓
$C_4H_4,$ butenyne

Answer

Correct option: D.

$C_4H_4,$ butenyne

d
Alkenynes contain a double bond and a triple bond. So, they must have at least four carbon atoms.

The first member of the family of alkenynes is butenyne. Its molecular formula is $C _4 H _4$.

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MCQ 971 Mark

Major product of above reaction is

Answer

Correct option: C.

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MCQ 981 Mark

$\xrightarrow[{hv}]{{NBS}}$ Product ;

Which product will not likely to form

Answer

Correct option: B.

b
In presence of $NBS$ , Allylic/Benzylic substitution take place

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MCQ 991 Mark

(image) $\xrightarrow[CC{{l}_{4}}]{HCl}X\xrightarrow{Aq.NaOH}Y\xrightarrow[\Delta ]{Conc.{{H}_{3}}P{{O}_{4}}}Z$ Major product is

A
$CH_3 -CH_2 -CH=CH_2$
✓
$CH_3 -CH=CH-CH_3$
C
$\begin{array}{*{20}{c}}
{C{H_3} - CH - CH = C{H_2}}\\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
D
$CH_2 =CH-CH=CH_2$

Answer

Correct option: B.

$CH_3 -CH=CH-CH_3$

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MCQ 1001 Mark

Reactant $(A)$ can be

A
B
C
✓
All of these

Answer

Correct option: D.

All of these

d
Source of this carbocation can be $(a), (b)$ and $(c).$

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MCQ 1011 Mark

Major product of the reaction is

Answer

Correct option: C.

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MCQ 1021 Mark

$\begin{array}{*{20}{c}}
{C{H_2} - C{O_2}K} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C{H_2} - C{O_2}K}
\end{array}\xrightarrow{{electrolysis}}\mathop {(A)}\limits_{\left( {major} \right)} $ (Kolbe electrolysis method)

Product $(A)$ of the reaction is

A
$CH_3 - CH_3$
✓
$CH_2 = CH_2$
C
$CH_3 -CH = CH_2$
D
none of these

Answer

Correct option: B.

$CH_2 = CH_2$

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MCQ 1031 Mark

Product $(C)$ of the reaction is

Answer

Correct option: C.

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MCQ 1041 Mark

Product $W$ is

Answer

Correct option: C.

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MCQ 1051 Mark

Methyl vinyl ether, $H_2C = CH -OCH_3$, reacts with $Br_2 /CH_3OH$. If methanol is reacting as water would, and if this reaction follows a typical mechanism of electrophilic addition, what would be the expected product ?

Answer

Correct option: B.

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MCQ 1061 Mark

$2, 4$ -hexadiyne $(C_6H_6)$ is allowed to react with $Li $ in $NH_3 (liq)$. The product obtained is treated with $1$ equivalent of $Cl_2$ in $CCl_4$. Which of the following constitutional isomers are possible products ?

A
$I$ and $II$
B
$II$ and $III$
C
$I$ and $V$
✓
$I$ and $III$

Answer

Correct option: D.

$I$ and $III$

d
$(d) \,1,2$ and $1,4-$ addition take place.

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MCQ 1071 Mark

Trans-cyclohexane- $1,2$ -diol can be obtained by the reaction of cyclohexene with

A
$KMnO_4$
B
$OsO_4$
✓
peroxy formic acid / $H_3O^+$
D
$SeO_2$

Answer

Correct option: C.

peroxy formic acid / $H_3O^+$

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MCQ 1081 Mark

The major product formed during the reaction of $1$ -methyl cyclopentene with $CH_3CO_3H$ is

Answer

Correct option: C.

c
$(c)$ Epoxide will form.

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MCQ 1091 Mark

Answer

Correct option: B.

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MCQ 1101 Mark

Product $(P)$ is

Answer

Correct option: B.

b
$(b)$ Alkoxymercuration-De-mercuration reaction

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MCQ 1111 Mark

What is the major product expected from the following reaction ?

Answer

Correct option: B.

b
$(b)$ cis-diol will form (syn addition takes place)

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MCQ 1121 Mark

$C{H_3} - CH = C{H_2}\xrightarrow[{(low\,\,conc.)}]{{B{r_2}/hv}}(A)$ ; Product $(A)$ of the reaction is

A
$\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_2} - Br}\\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
✓
$H_2C = CH - CH_2 -Br$
C
$\begin{array}{*{20}{c}}
{C{H_3} - C = C{H_2}}\\
|\\
{\,\,\,Br}
\end{array}$
D
$Br - CH_2 - CH_2 - CH_2 -Br$

Answer

Correct option: B.

$H_2C = CH - CH_2 -Br$

b
$(b)\, Br_2/hv$ (low cone.) (or) $N.B.S,$ Allylic free radical substitution reaction.

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MCQ 1131 Mark

Reagent $(A)$ in the reaction is

✓
$O_3 /Zn(H_2O)$
B
$HIO_4$
C
$CrO_3$
D
Cold dil. $KMnO_4$

Answer

Correct option: A.

$O_3 /Zn(H_2O)$

a
$(a)$ Alkene will be cleaved by ozonolysis.

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MCQ 1141 Mark

Product of the reaction is

Answer

Correct option: B.

b
$(b)$ cis-diol will form

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MCQ 1151 Mark

Which compound is a possible product from addition of $Br_2$ to $1$ -butene ?

Answer

Correct option: D.

d
$(d)$ Anti-addition take place.

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MCQ 1161 Mark

Addition of $Br_2$ to cis- $2$ -butene would give a product which is

A
achiral
✓
racemic
C
meso
D
optically active

Answer

Correct option: B.

racemic

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MCQ 1171 Mark

Addition of $Br_2$ to trans- $2$ -butene would give a product which is

A
achiral
B
racemic
✓
meso
D
optically active

Answer

Correct option: C.

meso

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MCQ 1181 Mark

Addition of $OsO_4$ to cyclopentene would give a product which is

A
achiral
B
racemic
✓
meso
D
optically active

Answer

Correct option: C.

meso

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MCQ 1191 Mark

Addition of $BH_3$ followed by $H_2O_2$ to trans- $2$ -butene would give a product which is

A
achiral
✓
racemic
C
meso
D
optically active

Answer

Correct option: B.

racemic

b
$(b)$ Hydroboration - oxidation reaction is a syn-addition.

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MCQ 1201 Mark

Reagent $A$ may be

A
$H_2O/H^+$
B
$BH_3 . THF/H_2O_2 -OH^-$
✓
$Hg(OCOCH_3)_2.H_2O/NaBH_4 .NaOH$
D
All are possible

Answer

Correct option: C.

$Hg(OCOCH_3)_2.H_2O/NaBH_4 .NaOH$

c
$(c)$ Oxymercuration - Demercuration reaction addition of $H_2O$ molecule is according to Markovnikoff's rule

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MCQ 1211 Mark

The major product of the following reaction is

$C{H_3} - CH = C{H_2} + HBr\xrightarrow{{{{({C_6}{H_5}CO)}_2}{O_2}}}$

✓
$CH_3 -CH_2 -CH_2 -Br$
B
$CH_3CH (Br)-CH_3$
C
$BrCH_2 - CH = CH_2$
D

Answer

Correct option: A.

$CH_3 -CH_2 -CH_2 -Br$

a
$(a)$ Anti-Markovnikoffs addition take place (Peroxide effect operates).

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MCQ 1221 Mark

Identify $(B)$

Answer

Correct option: B.

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MCQ 1231 Mark

Propene $CH_3CH = CH_2$ can be converted into $1$ -propanol by oxidation. Indicate which sets of reagents amongst the following is ideal to effect the above conversion ?

A
$KMnO_4$ (alkaline)
B
Osmium tetroxide $(OsO_4 /CH_2Cl_2)$
✓
$B_2H_6$ and alk. $H_2O_2$
D
$O_3 /Zn$

Answer

Correct option: C.

$B_2H_6$ and alk. $H_2O_2$

c
$(c)$ Hydroboration-oxidation reaction.

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MCQ 1241 Mark

The principal organic product formed in the reaction given below is

$C{H_2} = CH{(C{H_2})_8}COOH + HBr\xrightarrow{{peroxide}}....$

A
$CH_3 -CHBr(CH_2)_8COOH$
B
$CH_2 = CH(CH_2)_8COBr$
✓
$CH_2BrCH_2 (CH_2)_8COOH$
D
$CH_2 = CH (CH_2)_7CHBrCOOH$

Answer

Correct option: C.

$CH_2BrCH_2 (CH_2)_8COOH$

c
$(c)$ Anti-Markovnikoffs addition take place.

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MCQ 1251 Mark

Which of the following alkene on catalytic hydrogenation given cis and trans- isomer?

A
B
C
✓
all of these

Answer

Correct option: D.

all of these

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MCQ 1261 Mark

In the reaction of hydrogen bromide with an alkene (in the absence of peroxides), the first step of the reaction is the ................. to the alkene

A
fast addition of an electrophilic
✓
slow addition of an electrophile
C
fast addition of a nucleophilic
D
slow addition of a nucleophile

Answer

Correct option: B.

slow addition of an electrophile

b
$(b)$ Formation of carbocation is the rate determining step.

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MCQ 1271 Mark

Which of the following alcohols cannot be prepared from hydration of an alkene?

Answer

Correct option: D.

d
$(d)$ Corresponding alkene is not possible.

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MCQ 1281 Mark

Which of the species shown below is the most stable form of the intermediate in the electrophilic addition of $Cl_2$ in water to cyclohexene to form a halohydrin ?

Answer

Correct option: D.

d
$(d)$ Non-classical carbocation will form.

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MCQ 1291 Mark

The reaction, $(CH_3)_2C = CH_2 + B{{r}^{\centerdot }} \to (CH_3)_2 \overset{\centerdot }{\mathop{C}}\,- CH_2Br$

is an example of a/an ................ step in a radical chain reaction.

A
initiation
B
termination
✓
propagation
D
heterolytic cleavage

Answer

Correct option: C.

propagation

c
$(c)$ Attack of free radical on alkene is an propagation step.

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MCQ 1301 Mark

Which of the following most accurately describes the first step in the reaction of hydrogen chloride with $1-$ butene ?

Answer

Correct option: B.

b
$(b)$ Attack of alkene take place of $H - Cl$

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MCQ 1311 Mark

Which of the following best describes the flow of electrons in the acid-catalyzed dimerization of $(CH_3)_2C = CH_2$ ?

Answer

Correct option: A.

a
$(a)$ Carbocation formed will attacked by alkene.

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MCQ 1321 Mark

Hydroboration of $1$- methylcyclopentene using $B_2D_6$ , followed by treatment with alkaline hydrogen peroxide, gives

Answer

Correct option: A.

a
$(a)$ Hydroboration-oxidation take place (syn addition).

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MCQ 1331 Mark

Product $(B)$ of the reaction is

Answer

Correct option: B.

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MCQ 1341 Mark

In catalytic reduction of hydrocarbons which catalyst is mostly used

✓
$Pt /Ni$
B
$Pd$
C
$Si{O_2}$
D
Misch Metal

Answer

Correct option: A.

$Pt /Ni$

a
(a) $Pt./Ni$ is used in catalytic reduction of hydrocarbon.

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MCQ 1351 Mark

Gasoline is obtained from crude petroleum oil by its

✓
Fractional distillation
B
Vacuum distillation
C
Steam distillation
D
Pyrolysis

Answer

Correct option: A.

Fractional distillation

a
(a) Fractional distillation is used because the difference between the boiling point of different component is less.

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MCQ 1361 Mark

Which of the following does not give alkane

A
Reaction of $C{H_3}I$ with $Na$ in ether
B
Reaction of sodium acetate with sodalime
C
Electrolysis of concentrated sodium acetate solution
✓
Reaction of ethyl chloride with alco. $KOH$

Answer

Correct option: D.

Reaction of ethyl chloride with alco. $KOH$

d
(d) $C{H_3} - C{H_2} - Cl + \mathop {KOH}\limits_{{\rm{(alc}}{\rm{.)}}} \to \mathop {C{H_2} = C{H_2}}\limits_{{\rm{Ethene}}} + KCl + {H_2}O$

In presence of alc. $KOH$ dehydrohalogenation occur and alkene is formed.

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MCQ 1371 Mark

$LPG$ is a mixture of

A
${C_6}{H_{12}} + {C_6}{H_6}$
✓
${C_4}{H_{10}} + {C_3}{H_8}$
C
${C_2}{H_4} + {C_2}{H_2}$
D
${C_2}{H_4} + C{H_4}$

Answer

Correct option: B.

${C_4}{H_{10}} + {C_3}{H_8}$

b
(b) Liquefied petroleum gas is a mixture of ethane, propane and butane. The main component is butane.

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MCQ 1381 Mark

Carbon black, which is used in making printer's ink, is obtained by decomposition of

A
Acetylene
B
Benzene
C
Carbon tetrachloride
✓
Methane

Answer

Correct option: D.

Methane

d
(d) $C{{H}_{4}}+{{O}_{2}}\underset{\begin{smallmatrix}
\text{Limited} \\
\text{supply }
\\
\text{of air}
\end{smallmatrix}}{\mathop{\xrightarrow{\Delta }}}\,C+2{{H}_{2}}O$

It contains $98-99\%$ carbon. It is used in making black ink, paints and shoe polishes.

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MCQ 1391 Mark

The addition of tetraethyl lead to petrol

A
Lowers its octane number
✓
Raises its octane number
C
May raise or lower the octane number
D
Has no effect on octane number

Answer

Correct option: B.

Raises its octane number

b
(b)Tetraethyl lead is anti-knocking agent it increases the octane no. of the fuel.

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MCQ 1401 Mark

Knocking sound occurs in engine when fuel

A
Ignites slowly
✓
Ignites rapidly
C
Contains water
D
Is mixed with machine oil

Answer

Correct option: B.

Ignites rapidly

b
(b)Knocking - Sudden and irregular burning of the fuel mixture causing jerks against the piston and gives rise to violent sound. This is known as knocking.

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MCQ 1411 Mark

Petroleum is mainly a mixture of

✓
Alkanes
B
Cyclohexane
C
Benzenoid hydrocarbons
D
Alkenes

Answer

Correct option: A.

Alkanes

a
Petroleum is a mixture of a very large number of different hydrocarbons; the most commonly found molecules are alkanes (paraffins), cycloalkanes (naphthenes), aromatic hydrocarbons, or more complicated chemicals like asphaltenes.... They are the petroleum gases.

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MCQ 1421 Mark

Aqueous solution of the following compound on electrolysis gives ethane

A
Acetic acid
B
Acetamide
✓
Potassium acetate
D
Ethyl acetate

Answer

Correct option: C.

Potassium acetate

c
(c) $\mathop {2C{H_3}COOK}\limits_{{\rm{Potassium acetate}}} + 2{H_2}O\,\, \xrightarrow{Electrolysis} \,\,\mathop {C{H_3} - C{H_3} + 2C{O_2}}\limits_{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{Anode}}} + \mathop {2KOH + {H_2}}\limits_{\,\,\,\,\,\,\,\,\,\,\,\,{\rm{Cathode}}} $

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MCQ 1431 Mark

Which of the following does not decolourise bromine solution in carbon disulphide

A
Acetylene
B
Propene
✓
Ethane
D
Propyne

Answer

Correct option: C.

Ethane

c
(c)Ethane does not decolourise bromine solution because it is a saturated compound.

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MCQ 1441 Mark

Anhydrous sodium acetate on heating with sodalime gives

A
Acetic acid
✓
Methane
C
Calcium acetate
D
Ethane

Answer

Correct option: B.

Methane

b
(b) $\mathop {C{H_3}COONa}\limits_{{\rm{Sodium acetate}}} + NaOH \xrightarrow{CaO} \mathop {C{H_4}}\limits_{{\rm{Methane}}} + N{a_2}C{O_3}$

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MCQ 1451 Mark

Water gas is

A
$CO + C{O_2}$
B
$CO + {N_2}$
✓
$CO + {H_2}$
D
$CO + {N_2} + {H_2}$

Answer

Correct option: C.

$CO + {H_2}$

c
The mixture of carbon monoxide $( CO )$ and hydrogen $\left( H _2\right)$ is called water gas.

Syn gas is a mixture of $CO , CO _2$ and $H _2$.

Producer gas is a mixture of flammable gases (principally carbon monoxide and hydrogen) and nonflammable gases (mainly nitrogen and carbon dioxide).

Semi-water gas is a mixture of water gas and producer gas made by passing a mixture of air and steam through heated coke.

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MCQ 1461 Mark

A sample of gasoline contains $81\%$ iso-octane and $19\%$ $n-$ heptane. Its octane number will be

A
$19$
✓
$81$
C
$100$
D
$62$

Answer

Correct option: B.

$81$

b
(b) Octane number is related to the percentage of iso-octane since iso-octane is $81\%$ hence octane number is $81$.

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MCQ 1471 Mark

The natural petroleum contains

A
Saturated hydrocarbons
B
Cyclic saturated hydrocarbons
C
Compounds of sulphur
✓
All of these

Answer

Correct option: D.

All of these

d
The hydrocarbons in crude oil are mostly alkanes (paraffins), cycloalkanes (naphthenes) and various aromatic hydrocarbons while the other organic compounds contain nitrogen, oxygen and sulfur, and trace amounts of metals such as iron, nickel, copper and vanadium.

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MCQ 1481 Mark

The preparation of ethane by electrolysis of aqueous solution of potassium acetate is called as

A
Wurtz reaction
B
Sabatier-Senderen's reaction
✓
Kolbe's synthesis
D
Grignard reaction

Answer

Correct option: C.

Kolbe's synthesis

c
(c) $2C{H_3}COOK + 2{H_2}O\xrightarrow{{{\text{Electrolysis}}}}$ $\underbrace {2C{O_2} + C{H_3} - C{H_3}}_{Anode} + \underbrace {2KOH}_{cathode} + {H_2}$

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MCQ 1491 Mark

As the number of carbon atoms in a chain increases the boiling point of alkanes

✓
Increases
B
Decreases
C
Remains same
D
May increase or decrease

Answer

Correct option: A.

Increases

a
(a) Boiling point of alkanes increases with the number of carbon atoms because surface area increases which increases the Vander Waal forces.

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MCQ 1501 Mark

In the fractional distillation of crude petroleum

A
Petrol condenses at the bottom of the column
B
The gases condense at the top of the column
✓
High boiling constituents condense at the bottom of the column
D
High boiling constituents condense at the top of the column

Answer

Correct option: C.

High boiling constituents condense at the bottom of the column

c
It’s obvious.

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MCQ 1511 Mark

Which of the following is not an endothermic reaction

A
Dehydrogenation
B
Ethane to ethene
✓
Combustion of propane
D
Change of chlorine molecule into chlorine atoms.

Answer

Correct option: C.

Combustion of propane

c
(c)The enthalpy of combustion i.e., $\Delta H$ is always negative. It means combustion is an exothermic reaction.

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MCQ 1521 Mark

Gasoline is the name of

A
Crude oil
✓
The gaseous constituents of petroleum
C
The mixture of uncondensed gases produced in the distillation of crude oil
D
The mixture of the residue and gas oil obtained in the distillation of crude oil

Answer

Correct option: B.

The gaseous constituents of petroleum

b
Gasoline, also spelled gasolene, also called gas or petrol, mixture of volatile, flammable liquid hydrocarbons derived from petroleum and used as fuel for internal-combustion engines. It is also used as a solvent for oils and fats.

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MCQ 1531 Mark

In the process of cracking

A
Organic compounds decompose into their constituent elements
B
Hydrocarbons decompose into carbon and hydrogen
✓
High molecular weight organic compounds decompose to give low molecular weight organic compounds
D
Hydrocarbons yield alkyl radicals and hydrogen

Answer

Correct option: C.

High molecular weight organic compounds decompose to give low molecular weight organic compounds

c
It’s obvious.

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MCQ 1541 Mark

Octane number has $0$ value for

A
iso-octane
B
$n-$ hexane
✓
$n-$ heptane
D
iso-heptane

Answer

Correct option: C.

$n-$ heptane

c
$n$-heptane is defined as the zero point of the octane rating scale. $2,2,4-$Trimethylpentane has an octane rating of $100$ , whereas $n$-heptane has an octane rating of $0$. The octane number is based on an arbitrary scale which is a measure of its ability to resist knocking, as it burns on combustion.

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MCQ 1551 Mark

Dry distillation of sodium propanoate with sodalime gives

A
Propane
B
Propene
✓
Ethane
D
Ethene

Answer

Correct option: C.

Ethane

c
(c) $C{H_3}C{H_2}COONa + NaOH \,\,\, \xrightarrow{CaO} {C_2}{H_6} + N{a_2}C{O_3}$

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MCQ 1561 Mark

Which of the following fractions of petroleum refining contains kerosene ? (Boiling ranges in $^oC$ are given below)

A
$40 - 80$
B
$80 - 200$
✓
$200 - 300$
D
Above $300$

Answer

Correct option: C.

$200 - 300$

c
The fraction of petroleum refining containing Useful hydrocarbons like kerosene is found between a temperature $200-300^{\circ} C$. These products are highly volatile, have small molecules, have low boiling points, flow easily, and ignite easily.

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MCQ 1571 Mark

Methane can be prepared by

A
Wurtz's reaction
✓
Decarboxylation
C
Hydrogenation reaction
D
All of these

Answer

Correct option: B.

Decarboxylation

b
(b)$C{H_3}COONa + NaOH \xrightarrow{CaO} C{H_4} + N{a_2}C{O_3}$

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MCQ 1581 Mark

Which does not react with chlorine in dark

A
${C_2}{H_4}$
B
${C_2}{H_2}$
✓
$C{H_4}$
D
$C{H_3}CHO$

Answer

Correct option: C.

$C{H_4}$

c
$Cl _2$ fissure into the atoms of of Chlorine. Chlorine atoms contact to Methane and they led to the formation of $HCl$ and the radicals of Methane. So, methane does not react with Chlorine in dark.

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MCQ 1591 Mark

Which of the following method can be used for the preparation of methane

A
Wurtz reaction
B
Kolbe's reaction
✓
Reduction of alkyl halide
D
Hydrogenation of alkene

Answer

Correct option: C.

Reduction of alkyl halide

c
(c) $C{H_3} - Cl + 2H \xrightarrow{Zn/HCl} C{H_4} + HCl$

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MCQ 1601 Mark

Which hydrocarbon will be most stable

A
Methane
B
Ethane
C
Propane
✓
Butane

Answer

Correct option: D.

Butane

d
Longer chain alkanes are typically more stable (relatively, based on the number of carbons) compared with a shorter chain alkane. More branched compounds are typically more stable than straight chain alkanes with the same number of atoms.

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MCQ 1611 Mark

When sodium reacts with ethyl iodide, which of the following hydrocarbons is produced

A
Methane
B
Ethane
✓
Butane
D
Ethene

Answer

Correct option: C.

Butane

c
(c) Wurtz reaction

${C_2}{H_5} - I + 2Na + I - {C_2}{H_5} \xrightarrow[Ether]{Dry} \mathop {}\limits_{{\rm{Ether}}} \mathop {{C_2}{H_5} - {C_2}{H_5} + 2NaI}\limits_{{\rm{Butane}}} $

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MCQ 1621 Mark

$C{H_3}MgI$ will give methane with

A
${C_2}{H_5}OH$
B
$C{H_3} - C{H_2} - N{H_2}$
C
$C{H_3} - CO - C{H_3}$
✓
Both $(a)$ and $(b)$

Answer

Correct option: D.

Both $(a)$ and $(b)$

d
(d) $C{H_3}MgI + C{H_3} - C{H_2} - N{H_2} \to \,\,C{H_4} + C{H_3}C{H_2}NHMgI$

$C{H_3}MgI + {C_2}{H_5}OH \to C{H_4} + {C_2}{H_5}OMgI$

Alkyl group of Grignard’s reagent is involved in the formation of alkane.

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MCQ 1631 Mark

Propane$-1-$ol can be prepared from propene by its reaction with

A
$C{H_3}COOH$
B
${H_3}B{O_3}$
✓
${B_2}{H_6}/NaOH,{H_2}{O_2}$
D
${H_2}S{O_4}/{H_2}O$

Answer

Correct option: C.

${B_2}{H_6}/NaOH,{H_2}{O_2}$

c
It’s obvious.

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MCQ 1641 Mark

Successive alkanes differ by

✓
$>C{H_2}$
B
$>CH$
C
$ - \,\,C{H_3}$
D
${C_2}{H_4}$

Answer

Correct option: A.

$>C{H_2}$

a
successive members differ in mass by an extra methylene bridge $\left(- CH _2-\right.$ unit) inserted in the chain.

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MCQ 1651 Mark

Methane and ethane both can be prepared in one step by which of the following compound

A
${C_2}{H_4}$
B
$C{H_3}O$
✓
$C{H_3}Br$
D
$C{H_3}C{H_2}OH$

Answer

Correct option: C.

$C{H_3}Br$

c
(c) $C{H_3}Br + {H_2}\,\, \xrightarrow{LiAlH4} CH_4 $ (methane) $ \xrightarrow{Na} \,\,C{H_3} - C{H_3}$ (Ethane)

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MCQ 1661 Mark

Photochemical chlorination of alkane is initiated by a process of

A
Pyrolysis
B
Substitution
C
Cracking
✓
Homolysis

Answer

Correct option: D.

Homolysis

d
(d) Photochemical chlorination of alkane take place by free radical mechanism which are possible by Homolysis of $C -C$ bond

$C{l_2} \xrightarrow{hv} C{l^ \bullet } + C{l^ \bullet }$

$C{H_3} - C{H_3} + C{l^ \bullet } \to C{H_3}C{l^ \bullet } + \dot C{H_3}$

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MCQ 1671 Mark

A petroleum fraction having boiling range $70-200\,^oC$ and containing $6-10$ carbon atoms per molecule is called

A
Natural gas
B
Gas oil
✓
Gasoline
D
Kerosene

Answer

Correct option: C.

Gasoline

c
It’s obvious.

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MCQ 1681 Mark

Producer gas is a mixture of

✓
$CO$ and ${N_2}$
B
$C{O_2}$ and ${H_2}$
C
${N_2}$ and ${O_2}$
D
$C{H_4}$ and ${N_2}$

Answer

Correct option: A.

$CO$ and ${N_2}$

a
(a) Producer gas -$ CO\,{\rm{and \,}}{N_2}$

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MCQ 1691 Mark

The highest boiling point is expected for

A
$n - $butane
B
iso-octane
✓
$n - $octane
D
$2, 2, 3, 3- $tetramethyl butane

Answer

Correct option: C.

$n - $octane

c
(c) Among alkanes, boiling point increase with increasing molecular weight. For isomeric alkanes straight chain alkanes have higher boiling point than the branched alkanes.

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MCQ 1701 Mark

Which of the following is a good conductor of heat of electricity

A
Diamond
✓
Graphite
C
Anthracite
D
Charcoal

Answer

Correct option: B.

Graphite

b
(b) Graphite is a good conductor of heat of electricity.

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MCQ 1711 Mark

Which one of the following has the minimum boiling point

A
$1-$Butene
B
$1-$Butyne
C
$n-$Butane
✓
Isobutane

Answer

Correct option: D.

Isobutane

d
(d)Among the isomeric alkanes, the normal isomer has a higher boiling point than the branched chain isomer. The greater the branching of the chain, the lower is the boiling point. The $n-$alkane have larger surface area in comparison to branched chain isomer (as the shape approaches that of a sphere in the branched chain isomers). Thus, intermolecular forces are weaker in branched chain isomers, there fore they have lower point in comparision to straight chain isomers.

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MCQ 1721 Mark

The octane number of a sample of petrol is $40$. It means that its knocking property is equal to the mixture of

A
$40\%$ $n-$ heptane + $60\%$ iso-octane
B
$40\%$ petrol + $60\%$ iso-octane
✓
$60\%$ $n-$ heptane + $40\%$ iso-octane
D
$60\%$ petrol + $40\%$ iso-octane

Answer

Correct option: C.

$60\%$ $n-$ heptane + $40\%$ iso-octane

c
(c) Octane number of fuel is the percentage of iso- octane in mixture.

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MCQ 1731 Mark

When ethyl alcohol is heated with red phosphorus and $HI$, then which of the following is formed

✓
${C_2}{H_6}$
B
$C{H_4}$
C
${C_3}{H_8}$
D
${C_2}{H_4}$

Answer

Correct option: A.

${C_2}{H_6}$

a
(a) $\mathop {C{H_3}C{H_2} - OH}\limits_{{\text{Ethyl}}\,{\text{alcohol}}} + 2HI\xrightarrow{{Red\,P}}\mathop {C{H_3} - C{H_3}}\limits_{{\text{Ethane}}} + {H_2}O + {I_2}$

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MCQ 1741 Mark

In the Fischer-Tropsch synthesis of petrol..... and ..... are used as the raw materials

✓
${H_2};CO$
B
$C{H_4};{H_2}$
C
$C{H_4};C{H_3}OH$
D
$C{H_3}OH;CO$

Answer

Correct option: A.

${H_2};CO$

a
(a) Fischer-Tropsch process -

$\underbrace {CO + {H_2}}_{{\text{Water}}\,{\text{gas}}} + \mathop {{H_2}}\limits_{{\text{Excess}}} \mathop {\xrightarrow{{{\text{CO}}\,\,{\text{or}}\,{\text{Ni}}}}}\limits_{{\text{heat}}} \mathop {Mixure\,of\,hydrocarbons\,}\limits_{(Petrol)} + {H_2}O$

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MCQ 1751 Mark

On cracking petrol, we get

A
$C{H_4}$
B
${C_3}{H_6}$
✓
Both $(a)$ and $(b)$
D
$C{H_3} + C{H_4} + {C_2}{H_6} + {\text{ alcohols}}$

Answer

Correct option: C.

Both $(a)$ and $(b)$

c
(c) On cracking petrol gives smaller hydrocarbons like $CH_4$, $C_3H_6$.

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MCQ 1761 Mark

Cetane is a compound which has very good ignition property. Chemically it is

✓
$C{H_3}{(C{H_2})_{14}}C{H_3}$
B
${(C{H_3})_3}C{(C{H_2})_{11}}C{H_3}$
C
${C_{17}}{H_{34}}$
D
None of these

Answer

Correct option: A.

$C{H_3}{(C{H_2})_{14}}C{H_3}$

a
(a) Cetane is chemically hexadecane i.e,
$C{H_3}{(C{H_2})_{14}}C{H_3}$.

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MCQ 1771 Mark

The number of secondary hydrogens in $2, 2-$ dimethyl butane is

A
$8$
B
$6$
C
$4$
✓
$2$

Answer

Correct option: D.

$2$

d
(d) $\mathop {\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,H\,\,\,\,\,\,\,C{H_{3\,}}} \\
{|\,\,\,\,\,\,\,\,\,\,\,|} \\
{{H_3}C - C - C - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,H\,\,\,\,\,\,\,C{H_3}}
\end{array}}\limits_{2,2\,\dim ethyl\,bu\tan e} $

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MCQ 1781 Mark

An alkane (molecular weight $72$) forms only one monochlorinated product. Its formula is

✓
${(C{H_3})_4}C$
B
$C{H_3}{(C{H_2})_3}C{H_3}$
C
${(C{H_3})_2}CHC{H_2}C{H_3}$
D

Answer

Correct option: A.

${(C{H_3})_4}C$

a
(a) The alkane forms only one mono substituted product, it must have only one type of hydrogen atoms. there fore the alkane is $2, 2-$ dimethyl propane.

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MCQ 1791 Mark

The poisonous gas that comes out with petrol burning in a car is

A
$C{H_4}$
B
${C_2}{H_6}$
C
$C{O_2}$
✓
$CO$

Answer

Correct option: D.

$CO$

d
(d) On petrol burning $CO$ comes out which is so much poisonous gas.

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MCQ 1801 Mark

$\mathop {{C_6}{H_{14}}}\limits_{n - hexane} \xrightarrow{{A{l_2}{O_3}/\Delta }}(A)\xrightarrow{{(CO + HCl)/AlC{l_3}}}(B)$

Select the incorrect statement among following

A
Compound $'B'$ form silver mirror on reaction with $[Ag(NH_3)_2]OH$
✓
Molecularity of reaction during conversion from $'A'$ to $'B'$ is $'3'$
C
Compound $'A'$ can also be synthesised by reaction of benzene diazonium chloride with $H_3PO_2$
D
Compound $'B'$ give grey colour with aq. $HgCl_2$ solution

Answer

Correct option: B.

Molecularity of reaction during conversion from $'A'$ to $'B'$ is $'3'$

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MCQ 1811 Mark

Which has maximum $B.P.$ ?

Answer

Correct option: A.

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MCQ 1821 Mark

$CH_3Cl \to CH_4$
Above conversion can be achieved by

A
$Zn / H^+$
B
$LiAlH_4$
C
$Mg$ / (ether) then $H_2O$
✓
all of these

Answer

Correct option: D.

all of these

d
$C{H_3}Cl\xrightarrow[{\operatorname{Re} d.}]{{Zn/{H^ \oplus }}}C{H_4}$

$C{H_3}Cl\xrightarrow[{\operatorname{Re} d.}]{{LiAl{H_4}}}C{H_4}$

$C{H_3}Cl\xrightarrow[\begin{subarray}{l}
Dry \\
ether
\end{subarray} ]{{Mg}}\mathop {\mathop C\limits^{.\,.} }\limits^\Theta {H_3}\mathop {Mg}\limits^ \oplus Cl\xrightarrow{{\mathop H\limits^ \oplus OR}}C{H_4}$

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MCQ 1831 Mark

Products ; Comment up on optical activity of products

A
Diastereomers
✓
Racemic mixture
C
Meso
D
Optically pure enantiomer

Answer

Correct option: B.

Racemic mixture

b
Notice that the benzene ring is inert to these conditions; hydrogenation of benzene is discussed.

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MCQ 1841 Mark

Which of the following reactions do not represent the major product of given Birch reductions ?

A
$(i), (iii), (vi)$
✓
$(iv), (vi), (vii)$
C
$(iv), (v), (vi)$
D
$(i), (ii), (v), (vii)$

Answer

Correct option: B.

$(iv), (vi), (vii)$

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MCQ 1851 Mark

When comparing the hydrogenation of benzene with that of a hypothetical $1, 3,
5-$ cyclohexatriene, benzene .................... than the cyclohexatriene.

A
absorbs $152\, kJ /mol$ more heat
B
gives off $152\, kJ/mol$ more heat
C
absorbs $152\,kJ /mol$ less heat
✓
gives off $152\, kJ/mol$ less heat

Answer

Correct option: D.

gives off $152\, kJ/mol$ less heat

d
$(b)$ Benzene is aromatic therefore gives off $152 \,kJ/mol$ more heat.

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MCQ 1861 Mark

Which of the following ring compounds obeys Huckel's rule ?

A
$C_4H_4^{-1}$
B
$C_4H_4^{+1}$
✓
$C_4H_4^{-2}$
D
$C_4H_4$

Answer

Correct option: C.

$C_4H_4^{-2}$

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MCQ 1871 Mark

Caliene, $C_7 H_6$ , is expected to be a fairly polar aromatic molecule. Which of the following resonance forms contributes to the greatest extent to wards the real structure (resonance hybrid) of the molecule ?

Answer

Correct option: D.

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MCQ 1881 Mark

In the reaction given below, the major product formed is

Answer

Correct option: D.

d
$(d)$ More activated ring undergo electrophilic aromatic substitution.

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MCQ 1891 Mark

Suggest the best reaction conditions for the synthesis shown below.

A
$(1)\, HNO_3, H_2SO_2;$ then $(2)\, Br_2$
B
$(1)\, Br_2;$ then $(2)\, HNO_3 , H_2SO_2$
C
$(1)\, CH_3 Br, AlBr_3 ;$ then $(2) \,HNO_3 , H_2SO_3$
✓
$HNO_3 , H_2SO_2,$ then $(2)\, Br_2, FeBr_3$

Answer

Correct option: D.

$HNO_3 , H_2SO_2,$ then $(2)\, Br_2, FeBr_3$

d
$(d)$ Nitration following bromination.

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MCQ 1901 Mark

Which of the following benzene ring substituents is deactivating but orthopara directing ?

✓
$-N = O$
B
$-OCH_3$
C
$-COCH_3$
D
$- NO_2$

Answer

Correct option: A.

$-N = O$

a
$(a)\, - \ddot{N} = O$ group is $+M$ and $ -M$

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MCQ 1911 Mark

Predict the product of the following reaction.

Answer

Correct option: C.

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MCQ 1921 Mark

Which isomer of xylene can give three different monochloroderivatives ?

A
$o-$ xylene
✓
$m-$ xylene
C
$p-$ xylene
D
xylene cannot give a monochloro derivative

Answer

Correct option: B.

$m-$ xylene

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MCQ 1931 Mark

The rate of $o-$ nitration of the above compounds, $(I)$ toluene, $(II)\, 2-D-$ toluene and $(III) \,2, 6-D_2$ -toluene is in the following order

A
$I > II > III$
B
$II > I > III$
C
$III > I > II$
✓
The rate is the same for all the three compounds

Answer

Correct option: D.

The rate is the same for all the three compounds

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MCQ 1941 Mark

Which of the following is/are aromatic

A
Only $a$
B
$b, c$
C
$a, b,c$
✓
All

Answer

Correct option: D.

All

d
All of the following cyclic, plannar, conjugated compounds following Huckel rule.

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MCQ 1951 Mark

Identify the number of aromatic compounds

A
$4$
✓
$5$
C
$6$
D
$3$

Answer

Correct option: B.

$5$

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MCQ 1961 Mark

Which of the following statement is wrong for the given molecule

A
The given molecule is aromatic
✓
This molecule has $6\pi$ delocalized electrons.
C
This molecule has eight parallel pure $p-$ orbitals
D
This molecule is not planar

Answer

Correct option: B.

This molecule has $6\pi$ delocalized electrons.

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MCQ 1971 Mark

$Ph - MgCl\xrightarrow{{Hydrolysis}}$ Product

Product will be

Answer

Correct option: B.

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MCQ 1981 Mark

What is the major product of following reaction

Answer

Correct option: B.

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MCQ 1991 Mark

Aromaticity is present in

Answer

Correct option: C.

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MCQ 2001 Mark

Number of $\sigma $ and $\pi $ bonds in benzophenone is

A
$24, 6$
B
$24, 7$
C
$25, 6$
✓
$25, 7$

Answer

Correct option: D.

$25, 7$

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MCQ 2011 Mark

In the following reaction ${C_6}{H_5}C{H_2}Br\xrightarrow[{(ii){H_3}{O^ + }}]{{(i)Mg.\,Ether}}X$

Product $X$ is

✓
$C_6H_5CH_3$
B
$C_6H_5CH_2OH$
C
$C_6H_5CH_2CH_2C_6H_5$
D
$C_6H_5CH_2OCH_2C_6H_5$

Answer

Correct option: A.

$C_6H_5CH_3$

a
$C _6 H _5 CH _2 Br \stackrel{ Mg \text { Ether }}{\longrightarrow} \underset{Grignard\,\, Reagent}{C _6 H _5 CH _2 MgBr} \rightarrow C _6 H _5 CH _3+ Mg ( Br )( OH )$

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MCQ 2021 Mark

$\,$

✓
B
C
D
None

Answer

Correct option: A.

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MCQ 2031 Mark

During mixed acid nitration of benzene Conc. $HNO_3$ behaves like

A
Acid
✓
Base
C
Catalyst
D
Electrophile

Answer

Correct option: B.

Base

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MCQ 2041 Mark

Which of the following does not give friedel-craft reaction ?

✓
Aniline
B
Chlorobenzene
C
Anisole
D
Both $(A)$ and $(B)$

Answer

Correct option: A.

Aniline

a
Aniline does give $FCR$ due to salt formation with $AlCl_3.$ Due to this nitrogen of aniline becomes strong $EWG.$

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MCQ 2051 Mark

The best method to introduce fluorine in benzene ring as a substituent is

A
Fluorination by electrophilic substitution
✓
Balz schiemann reaction
C
Gattermann reaction
D
Swart's reaction

Answer

Correct option: B.

Balz schiemann reaction

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MCQ 2061 Mark

$x$ is

Answer

Correct option: A.

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MCQ 2071 Mark

$Z$ is

Answer

Correct option: A.

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MCQ 2081 Mark

Which of the following reaction is not an example of addition reaction

Answer

Correct option: B.

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MCQ 2091 Mark

In which of the following $C-Cl$ bond length is minimum ?

Answer

Correct option: C.

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MCQ 2101 Mark

benzen + $CH_3-CH_2-CH_2-Cl$ $\xrightarrow{{AlC{l_3}}}$ the product

Answer

Correct option: C.

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MCQ 2111 Mark

Which is not formed in the given reaction

A
✓
C
$CH_3 -CH_3$
D

Answer

Correct option: B.

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MCQ 2121 Mark

Which of the following is Aromatic

Answer

Correct option: D.

d
cyclic Resonance presence with $6 \pi$ $\overline{\mathrm{es}}$ in Resonance $\therefore$ this is aromatic

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MCQ 2131 Mark

Which of the following undergo friedal craft reaction

Answer

Correct option: D.

d
$-NO_2 , -CHO, NH_2$ If- group attached to benzene then friedal craft Reaction not possible

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MCQ 2141 Mark

$\begin{array}{*{20}{c}}
{C{H_2} - CH_2} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,} \\
{Cl\,\,\,\,\,\,\,\,\,\,\,Cl\,\,\,\,}
\end{array}$ $\xrightarrow[{(ii)NaN{H_2}}]{{(i)Alc.KOH}}A\xrightarrow{{\operatorname{Re} d\,hot\,Fe\,tube}}B$

Identify product $B$ in above reaction sequence

A
$HC \equiv CH$
✓
C
D

Answer

Correct option: B.

b
$\begin{array}{*{20}{c}}
{C{H_2} - C{H_2}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,} \\
{\,\,Cl\,\,\,\,\,\,\,\,\,\,Cl\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$ $\xrightarrow[{(ii)\,NaN{H_2}}]{{(i)\,Alc.\,KOH}}$ $HC \equiv CH\xrightarrow{{\operatorname{Re} d\,hote\,tube}}$ (figure)

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MCQ 2151 Mark

Which of the following reaction is called as wurtz- fittig reaction

Answer

Correct option: D.

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MCQ 2161 Mark

Chlorination of Benzene in the presence of sunlight gives

A
Hexachlorobenzene
✓
Benzene Hexachloride
C
Chlorobenzene
D
$1, 3, 5-$ trichlorocyclohexane

Answer

Correct option: B.

Benzene Hexachloride

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MCQ 2171 Mark

Which among the following statement is not correct for above reaction ?

A
Product $P$ is known as Benzene Hexachloride
✓
Product $P$ is aromatic
C
Product $P$ is used as an insecticide
D
The above reaction is an example of Free radical Addition Reaction

Answer

Correct option: B.

Product $P$ is aromatic

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MCQ 2181 Mark

In which of the following compound electrophilic attacks at ortho and para positions:

Answer

Correct option: A.

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MCQ 2191 Mark

Which of the following species is not aromatic

Answer

Correct option: B.

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MCQ 2201 Mark

Which of the following species is not aromatic

Answer

Correct option: B.

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MCQ 2211 Mark

The total number of benzene derivatives with molecular formula $C_6H_3Cl_3$ is

A
$2$
✓
$3$
C
$4$
D
$5$

Answer

Correct option: B.

$3$

b
The total number of benzene derivatives with the molecular formula $\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{Cl}_{3}$ is 3 .

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MCQ 2221 Mark

Which of the following is aromatic compound ?

Answer

Correct option: B.

b
due to Huckle rule

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MCQ 2231 Mark

benzene $ + \,C{H_2}C{l_2}\,\xrightarrow{{AlCl}}\,A$, $'A'$ is

A
B
✓
D
Benzene

Answer

Correct option: C.

c
Correct option is ($C$ )

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MCQ 2241 Mark

Which of the following can not react with $NaHCO_3$

A
B
C
✓
All

Answer

Correct option: D.

All

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MCQ 2251 Mark

How many products will be formed in above reaction ?

A
$2$
✓
$4$
C
$3$
D
$6$

Answer

Correct option: B.

$4$

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MCQ 2261 Mark

Product of the reacion is

✓
Racemic
B
Diastereomers
C
Meso
D
Pure enantiomers

Answer

Correct option: A.

Racemic

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MCQ 2271 Mark

cis- $2$ -butene $\xrightarrow[{Peroxide}]{{HBr}}$ product ; Product of the reaction is

✓
Racemic
B
Diastereomer
C
Meso
D
$E$ anq $Z$ isomer

Answer

Correct option: A.

Racemic

a
$\begin{array}{*{20}{c}}
{C{H_3} - C{H_2} - \mathop C\limits^* H - C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Br}
\end{array}$ (racemic mixture)

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MCQ 2281 Mark

Rate of reaction towards reduction using $(H_2 /Pt)$

✓
$a > b$
B
$a = b$
C
$b > a$
D
Reduction of given molecule is not possible

Answer

Correct option: A.

$a > b$

a
$(a)$ Less steric hinderance site will be attacked. Approach of $H_2$ is more hindered in $(b)$.

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MCQ 2291 Mark

Product is

Answer

Correct option: B.

b
$(b)$ Oxidation take place i.e., epoxidation

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MCQ 2301 Mark

Major product of the given reaction is

$H_2C = CH - CH_2 - I \xrightarrow[CC{{l}_{4}}]{HI(excess)}$

A
$\begin{matrix}
C{{H}_{3}}-CH-C{{H}_{2}} \\
\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,| \\
\,\,\,\,\,\,\,\,I\,\,\,\,\,\,\,\,\,\,\,I \\
\end{matrix}$
✓
$\begin{matrix}
C{{H}_{3}}-CH-C{{H}_{3}} \\
|\,\,\,\,\, \\
I\,\,\,\,\,\, \\
\end{matrix}$
C
$CH_3 - CH_2 - CH_2 - I$
D
$I - CH_2 - CdH_2 - CH_2 - I$

Answer

Correct option: B.

$\begin{matrix}
C{{H}_{3}}-CH-C{{H}_{3}} \\
|\,\,\,\,\, \\
I\,\,\,\,\,\, \\
\end{matrix}$

b
${H_2}C = CH - C{H_2} - I\xrightarrow[{M.Rule}]{{H - I}}$ $\mathop {\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_2}} \\
{\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,I\,\,\,\,\,\,\,\,\,\,\,I\,}
\end{array}}\limits_{(unstable)} \xrightarrow{{( - {I_2})}}$ $C{H_3} - CH = C{H_2}\xrightarrow[{M.Rule}]{{H - I}}\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_3}} \\
{|\,\,\,\,} \\
{I\,\,\,\,}
\end{array}$

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MCQ 2311 Mark

Major product of the given reaction is

A
B
✓
D
$\begin{matrix}
C{{H}_{3}}\,\,\, \\
|\,\,\,\,\,\,\,\,\,\, \\
{{H}_{2}}C=C-C{{H}_{2}}-C{{H}_{2}}-C{{H}_{3}} \\
\end{matrix}$

Answer

Correct option: C.

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MCQ 2321 Mark

Product $(P)$ is

Answer

Correct option: D.

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MCQ 2331 Mark

Product $(A)$ of the reaction is

✓
B
C
D
None of these

Answer

Correct option: A.

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MCQ 2341 Mark

Product $(A)$ is

Answer

Correct option: B.

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MCQ 2351 Mark

Product $(Z)$ is

Answer

Correct option: C.

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MCQ 2361 Mark

The reaction of propene with $HOCl$ proceeds via the addition of

A
$H^+$ in the first step
✓
$Cl^+$ in the first step
C
$\mathop O\limits^\Theta H$ in the first step
D
$Cl^+$ and $\mathop O\limits^\Theta H$ in the single step

Answer

Correct option: B.

$Cl^+$ in the first step

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MCQ 2371 Mark

Ozonolysis products of an olefin are $OHC-CHO$ and $OHC-CH_2-CH_2-CHO$, the olefin is

Answer

Correct option: C.

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MCQ 2381 Mark

$\begin{array}{*{20}{c}}
{C{H_3} - C{H_2} - CH - C{H_3}\xrightarrow[{KOH}]{{Alc.}}\mathop X\limits_{\left( {{\text{major}}} \right)} \,;} \\
{\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}\,$

$\begin{array}{*{20}{c}}
{C{H_3} - C{H_2} - CH - C{H_3}\xrightarrow[\Delta ]{{EtoNa}}\mathop {{\text{ }}Y}\limits_{\left( {{\text{major}}} \right)} } \\
{{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} |{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} \,\,\,\,\,{\mkern 1mu} \,\,\,\,{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} } \\
{{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} \mathop {{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} \,\,\,\,\,\,\,NM{e_3}\,\,\,\,\,\,\,{\mkern 1mu} }\limits_{\,\,\,\,\,\,\,\,\,\, \oplus \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} }
\end{array}{\mkern 1mu} $

Product $(X)$ and $(Y)$ respectively is

A
$1-$ butene, trans $2-$ butene
B
$1-$ butene, cis $-2-$ butene
C
cis $-2-$ butene, $1-$ butene
✓
trans $2-$ butene, $1-$ butene

Answer

Correct option: D.

trans $2-$ butene, $1-$ butene

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MCQ 2391 Mark

Arrange the above in the decreasing order of reactivity towards $HBr$

A
$a > b > c$
✓
$b > a > c$
C
$b > c > a$
D
$a > c > b$

Answer

Correct option: B.

$b > a > c$

b
$(b)$ Formation of carbocation is the rate determining step more the stable carbocation more is the reactivity toward $HBr$

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MCQ 2401 Mark

In which of the following reaction $CO_2$ gas will not be released ?

A
$CH_2=CH-CH_3$ $\xrightarrow{{{O_3}/{H_2}O}}$
B
✓
D
$C{H_3} - C \equiv CH\,\xrightarrow[{(ii)\,{H_2}O}]{{(i)\,KMn{O_4} + KOH}}$

Answer

Correct option: C.

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MCQ 2411 Mark

Which of the following alkene is most stable

A
$(CH_3)_3 C -CH = CH_2$
B
$CH_2 = CH_2$
✓
$(CH_3)_2 C = CH_2$
D
$CH_3 -CH = CH_2$

Answer

Correct option: C.

$(CH_3)_2 C = CH_2$

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MCQ 2421 Mark

Which of the following Alkane cannot be prepared by Hydrogenation of olefin

A
Propane
B
Isobutane
C
Isopentane
✓
Neopentane

Answer

Correct option: D.

Neopentane

d
$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,C{H_3}} \\
| \\
{C{H_3} - C - C{H_3}} \\
| \\
{\,\,\,\,\,C{H_3}}
\end{array} \to $ Neopentane cannot be prepared by Hydrogenation of olefin due to non availability of $\mathrm{H}$ that can be replaced and double bond can be placed between $2$ carbon atom

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MCQ 2431 Mark

Which reaction has the lowest $\Delta {{G}^{\begin{smallmatrix}
+ \\
+
\end{smallmatrix}}}$ or (Activation-Energy)?

Answer

Correct option: D.

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MCQ 2441 Mark

Energy profile diagram for dehydration of $2$ -butanol using conc. $H_2SO_4$ is given below

Product $(b)$ of above reaction is

A
$1$ -butene
✓
$cis-2$ -butene
C
$trans-2$ -butene
D
$iso$ -butene

Answer

Correct option: B.

$cis-2$ -butene

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MCQ 2451 Mark

How many alkene on catalytic hydrogenation given isopentane as a product ?

A
$2$
✓
$3$
C
$4$
D
$5$

Answer

Correct option: B.

$3$

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MCQ 2461 Mark

Which of the following would not rearrange to a more stable form ?

Answer

Correct option: C.

c
is stable carbocation due to presence of $\sigma $ -resonance so it will not rearrange.

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MCQ 2471 Mark

Ethylene react with $Br_2$ give $1,2-$ Dibromoethane intermediate of reaction is

A
$\begin{array}{*{20}{c}}
{C{H_2} - \mathop C\limits^ \oplus {H_2}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
✓
C
$Br - CH = \mathop C\limits^ \oplus H$
D

Answer

Correct option: B.

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MCQ 2481 Mark

(Image) $\xrightarrow{{electrolysis}}$ Product is

A
✓
$H - C \equiv C - H$
C
D

Answer

Correct option: B.

$H - C \equiv C - H$

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MCQ 2491 Mark

The homologue of ethyne is

A
${C_2}{H_4}$
B
${C_2}{H_6}$
C
${C_3}{H_8}$
✓
${C_3}{H_4}$

Answer

Correct option: D.

${C_3}{H_4}$

d
(d)${C_2}{H_2}$ and ${C_3}{H_4}$ are homologue because they differ by $ - C{H_2}$ group. Both have triple bond in their molecule.

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MCQ 2501 Mark

When acetylene reacts with $HCl $ in the presence of $HgC{l_2}$, the product is

A
Methyl chloride
B
Dichloroethane
✓
Vinyl chloride
D
Ethylidine chloride

Answer

Correct option: C.

Vinyl chloride

c
(c) $CH \equiv CH + HCl\xrightarrow{{HgC{l_2}}}\mathop {C{H_2} = CH - Cl}\limits_{{\text{Vinyl chloride}}} $

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MCQ 2511 Mark

Propyne on polymerisation gives

✓
Mesitylene
B
Benzene
C
Ethyl benzene
D
Propyl benzene

Answer

Correct option: A.

Mesitylene

a
(a)

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MCQ 2521 Mark

Which of the following catalyst is used in the polymerisation of $CH \equiv CH$ to ${C_6}{H_6}$

✓
$AlC{l_3}$
B
$HgS{O_4}$
C
$NbC{l_3}$
D
$HCl$

Answer

Correct option: A.

$AlC{l_3}$

a
(a) $3CH \equiv CH\mathop {\xrightarrow{{{\text{Hot}}\,Cu\,{\text{tube}}}}}\limits_{AlC{l_3}} \,\,\,\,\,\begin{array}{*{20}{c}}
\end{array}\,\,\,\,\,\,\,\,\,\,\,\,\,\,$

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MCQ 2531 Mark

$KMn{O_4}$ will oxidise acetylene to

A
Ethylene glycol
B
Ethyl alcohol
✓
Oxalic acid
D
Acetic acid

Answer

Correct option: C.

Oxalic acid

c
(c) $\mathop {\begin{array}{*{20}{c}}
{CH} \\
{|||\,\,\,\,} \\
{CH}
\end{array}}\limits_{Acetylene} \xrightarrow{{KMn{O_2}}}\mathop {\begin{array}{*{20}{c}}
{COOH} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,} \\
{COOH}
\end{array}}\limits_{Oxalic\,acid} $

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MCQ 2541 Mark

$1, 2-$dibromoethane when heated with alcoholic potash gives

A
Ethane
✓
Acetylene
C
Ethylene
D
Methane

Answer

Correct option: B.

Acetylene

b
(b) $\mathop {|\,\,\,\,\,\,\,\,\,\,}\limits_{C{H_2}Br}^{C{H_2}Br} + 2KOH{\text{ (alcoholic) }}\xrightarrow{\Delta }CH \equiv CH + 2KBr + 2{H_2}O$

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MCQ 2551 Mark

Which of the following is not a member of homologous series

A
Ethene
B
$1-$butene
C
$2-$butene
✓
$2-$butyne

Answer

Correct option: D.

$2-$butyne

d
(d) All are alkenes but $2-$butyne is not.

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MCQ 2561 Mark

What is the product when $2-$butyne is treated with liquid $N{H_3}$ in presence of lithium

A
$n-$butane
B
cis$-2-$butene
✓
trans$-2-$butene
D
$1-$butene

Answer

Correct option: C.

trans$-2-$butene

c
(c) Reduction of alkynes with liquid $N{H_3}/Li$ gives trans alkenes.

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MCQ 2571 Mark

Distinction in pentene$-1$ and pentyne$-1$ is done by

✓
${[Ag{(N{H_3})_2}]^ + }$
B
Conc. ${H_2}S{O_4}$
C
$HCl$
D
$B{r_2}$

Answer

Correct option: A.

${[Ag{(N{H_3})_2}]^ + }$

a
$1$-Pentene does not react with Tollen's reagent.

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MCQ 2581 Mark

A mixture of ethane, ethene and ethyne is passed through ammoniacal $AgN{O_3}$ solution. The gases which remain unreacted are

✓
Ethane and ethene
B
Ethane and ethyne
C
Ethene and ethyne
D
Ethane only

Answer

Correct option: A.

Ethane and ethene

a
(a) Ethyne reacts with ammonical $AgN{O_3}$to give white ppt of silver acetylide while ethane and ethene do not react because acidic hydrogen is absent.

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MCQ 2591 Mark

In its reaction with silver nitrate acetylene shows

A
Oxidising property
B
Reducing property
C
Basic property
✓
Acidic property

Answer

Correct option: D.

Acidic property

d
(d)Acidic property because $H$ atoms are replaced by Silver metal atoms.

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MCQ 2601 Mark

Simplest alkyne is represented by

A
$CH$
B
$C{H_2}$
✓
${C_2}{H_2}$
D
${C_2}{H_4}$

Answer

Correct option: C.

${C_2}{H_2}$

c
The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula $C _{ n } H _{2 n -2}$ Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to $C _2 H _2$ known formally as ethyne using $IUPAC$ nomenclature.

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MCQ 2611 Mark

Carbide, which react with water to give propyne is

A
$Ca{C_2}$
B
$SiC$
✓
$M{g_2}{C_3}$
D
$A{l_4}{C_3}$(e)$B{e_2}C$

Answer

Correct option: C.

$M{g_2}{C_3}$

c
(c)$M{g_2}{C_3} + 4{H_2}O \to C{H_3}C \equiv CH + 2Mg{(OH)_2}$

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MCQ 2621 Mark

Hydrocarbon ${C_6}{H_6}$ decolourise $B{r_2}$ water and gives ppt. with ammonical $AgN{O_3}$ Hydrocarbon can be

A
$1, 3, 5 -$Cyclohexatriene
B
$1, 5- $Hexadiyne
C
$2, 4-$ Hexadiyne
✓
None

Answer

Correct option: D.

None

d
(d) Because Ammonical $AgN{O_3}$ reduce $C \equiv CH$ bond of yne.

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MCQ 2631 Mark

Order of reactivity of ${C_2}{H_6},{C_2}{H_4}$ and ${C_2}{H_2}$ is

A
${C_2}{H_6} > {C_2}{H_4} > {C_2}{H_2}$
B
${C_2}{H_2} > {C_2}{H_6} > {C_2}{H_4}$
✓
${C_2}{H_2} > {C_2}{H_4} > {C_2}{H_6}$
D
All are equally reactive

Answer

Correct option: C.

${C_2}{H_2} > {C_2}{H_4} > {C_2}{H_6}$

c
(c)Unsaturated hydrocarbons are more reactive than saturated hydrocarbons. Among ethyne $({C_2}{H_2})$ and ethene $({C_2}{H_4})$ the later is more reactive as $C \equiv C$ triple bond is quite strong bond and therefore ethyne generally require catalysts (like $H{g^{2 + }}$ etc) in its reactions.

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MCQ 2641 Mark

$C{H_3}C \equiv CC{H_3}\mathop {\xrightarrow{{(i){\text{ }}X}}}\limits_{(ii){H_2}O/Zn}$

$\begin{array}{*{20}{c}}
{C{H_3} - C - C - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{O\,\,\,\,\,\,\,\,\,O}
\end{array}$ $X$ in the above reaction is

A
$HN{O_3}$
B
${O_2}$
✓
${O_3}$
D
$KMn{O_4}$

Answer

Correct option: C.

${O_3}$

c
(c)$C{H_3} - C \equiv C - C{H_3}\mathop {\xrightarrow{{{\text{(i)}}\,{O_3}}}}\limits_{{\text{(ii)}}\,Zn/{H_2}O} C{H_3} - \mathop {\mathop C\limits_{||} }\limits_O - \mathop {\mathop C\limits_{||} }\limits_O - C{H_3}$

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MCQ 2651 Mark

In the reaction $HC \equiv CH + 2AgN{O_3}\xrightarrow{{N{H_4}OH}}X + 2N{H_4}N{O_3} + 2{H_2}O$ :‘$X$’ is

A
$A{g_2}C$
✓
$A{g_2}{C_2}$
C
$AgC$
D
$AgOH$

Answer

Correct option: B.

$A{g_2}{C_2}$

b
(b) $HC \equiv CH + 2AgN{O_3}\xrightarrow{{N{H_4}OH}}$ $Ag - C \equiv C - Ag + 2N{H_4}N{O_3} + 2{H_2}O$

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MCQ 2661 Mark

Acetylene reacts with $HCN$ in the presence of $Ba{(CN)_2}$ to yield

A
$1, 1-$dicyanoethane
B
$1, 2-$dicyanoethane
✓
Vinyl cyanide
D
None of these

Answer

Correct option: C.

Vinyl cyanide

c
(c) $\mathop {CH \equiv CH + HCN}\limits_{{\text{Acetylene}}} \xrightarrow{{Ba{{(CN)}_2}}}\mathop {C{H_2} = CHCN}\limits_{{\text{Vinyl cyanide}}} $

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MCQ 2671 Mark

$Ca{C_2} + {H_2}O \to A\xrightarrow{{{H_2}S{O_4}/HgS{O_4}}}B$ Identify $A$ and $B$ in the given reaction

✓
${C_2}{H_2}$ and $C{H_3}CHO$
B
$C{H_4}$ and $HCOOH$
C
${C_2}{H_4}$ and$C{H_3}COOH$
D
${C_2}{H_2}$ and $C{H_3}COOH$

Answer

Correct option: A.

${C_2}{H_2}$ and $C{H_3}CHO$

a
(a)Wohler reaction :

$Ca{C_2} + 2{H_2}O\xrightarrow{{}}{C_2}{H_2} + Ca{(OH)_2}$

$\mathop {{C_2}{H_2}}\limits_{{\text{Acetylene}}} \mathop {\xrightarrow{{dil.\,{H_2}S{O_4}/HgS{O_4}}}}\limits_{{{60}^o}C} \mathop {[C{H_2} = CHOH]}\limits_{{\text{Unstable}}} \to \mathop {C{H_3}CHO}\limits_{{\text{Acetaldehyde}}} $

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MCQ 2681 Mark

What is formed when calcium carbide react with heavy water

✓
${C_2}{D_2}$
B
$Ca{D_2}$
C
$Ca{D_2}O$
D
$C{D_2}$

Answer

Correct option: A.

${C_2}{D_2}$

a
$\mathop {Ca{C_2}}\limits_{{\text{calcium carbide}}} + \mathop {2{D_2}O}\limits_{{\text{heary water}}} \xrightarrow{{}}{C_2}{D_2} + Ca{(OD)_2}$

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MCQ 2691 Mark

When acetylene is reacted with $HBr$, we get

A
Methyl bromide
B
Ethyl bromide
C
Ethylene bromide
✓
Ethylidene bromide

Answer

Correct option: D.

Ethylidene bromide

d
(d) $CH \equiv CH\xrightarrow{{HBr}}C{H_2} = CH - Br\xrightarrow{{HBr}}$

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MCQ 2701 Mark

$CH \equiv CH + HBr \to X,$ product $X$ is

A
Ethylene bromide
✓
Vinyl bromide
C
Bromo ethane
D
Ethyledine bromide

Answer

Correct option: B.

Vinyl bromide

b
(b) $\mathop {CH \equiv CH + HBr}\limits_{{\rm{Acetylene}}} \to \,\,\,\mathop {C{H_2} = CHBr}\limits_{{\rm{Vinyl bromide}}} $

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MCQ 2711 Mark

Which of the following compound do not release $CO_2$ on oxidative ozonolysis

A
$1-$ butene
✓
$2-$ butyne
C
Propyne
D
Ethene

Answer

Correct option: B.

$2-$ butyne

b
Terminal alkene & alkyne release $CO_2$ on oxidative ozonolysis

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MCQ 2721 Mark

$1$-butyne can be distinguished from $2$-butyne by

A
$H_2/Pd\ BaSO_4$
B
$Br_2 / H_2O$
✓
$Cu_2Cl_2/NH_4OH$
D
Bayer's reagent

Answer

Correct option: C.

$Cu_2Cl_2/NH_4OH$

c
$C{{H}_{3}}-C{{H}_{2}}-C\equiv CH\xrightarrow{C{{u}_{2}}C{{l}_{2}}/N{{H}_{4}}OH}$

$C{{H}_{3}}-C{{H}_{2}}-C\equiv \overset{\Theta }{\mathop{C}}\,\,\overset{\oplus }{\mathop{C}}\,u\,\,(\operatorname{Re}d\,Coloured)$

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MCQ 2731 Mark

Product $A$ is major

A
$H_2C = CH - CH = CH_2$
✓
$CH_3 - C \equiv C - CH_3$
C
$CH_3 - CH_2 - C \equiv CH$
D
$CH_3 - CH = C = CH_2$

Answer

Correct option: B.

$CH_3 - C \equiv C - CH_3$

b
Bromination followed by dehydrohalogenation

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MCQ 2741 Mark

What is final product $Ph - C \equiv CH\xrightarrow[{Hgs{o_4}}]{{dil{H_2}S{O_4}}}\Pr oduct$

✓
$\,\,\,\begin{array}{*{20}{c}}
O \\ {||\,} \\
{Ph - C - C{H_3}}
\end{array}$
B
$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||} \\
{Ph - C{H_2} - C - H}
\end{array}$
C
$Ph-CH_2-CH_3$
D
$\,\,\,\begin{array}{*{20}{c}} {OH} \\ {|\,\,\,\,\,\,\,} \\ {Ph - CH - C{H_3}} \end{array}$

Answer

Correct option: A.

$\,\,\,\begin{array}{*{20}{c}}
O \\ {||\,} \\
{Ph - C - C{H_3}}
\end{array}$

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MCQ 2751 Mark

Which of the following decolorise $Br_2$ water solution

A
B
$CH_3-CH_2-OH$
✓
$HC \equiv CH$
D
$CH_3-CH_2-Cl$

Answer

Correct option: C.

$HC \equiv CH$

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MCQ 2761 Mark

In the reaction sequence

$C{H_3} - C \equiv CH\xrightarrow[{Dry\,ether}]{{C{H_3}MgBr}}C{H_4} + (A)\xrightarrow[{(ii)\,{H_2}O/{H^ + }}]{{(ii)\,C{O_2}}}(B),(B)$ will be

A
$C{H_3} - C \equiv C - C{H_3}$
B
$C{H_3} - C \equiv C - MgBr$
✓
$C{H_3} - C \equiv C - COOH$
D
$CH_3 -CH = CH -COOH$

Answer

Correct option: C.

$C{H_3} - C \equiv C - COOH$

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MCQ 2771 Mark

$CH_3-C \equiv C-O-CH_3 \xrightarrow{{dil.\,{H_2}S{O_4},HgS{O_4}}}$ major product

Answer

Correct option: B.

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MCQ 2781 Mark

$C_6H_5-C \equiv C-CH_3 \xrightarrow[{{H_2}S{O_4}}]{{HgS{O_4},\,{H_2}O}} A$

Major Product $(A)$ will be

✓
B
C
$\begin{array}{*{20}{c}}
{{C_6}{H_5} - C = CH - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{OH\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$
D
$\begin{array}{*{20}{c}}
{{C_6}{H_5} - CH = C - C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$

Answer

Correct option: A.

a
Addition of $H_2O$ according to Markownikoff's rule without rearrangement of carbocation

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MCQ 2791 Mark

(image) $\xrightarrow{\Delta }X;X$ can also be formed by

A
$CH_3-CH_2-CH_2-Cl \xrightarrow{{LiAl{H_4}}}$
B
$CH_3-CH_2-COOH \xrightarrow{{P + HI}}$
✓
$C{H_3} - C \equiv CH\xrightarrow[{{H_2}O}]{{H{g^{ + 2}}}}$
D
All

Answer

Correct option: C.

$C{H_3} - C \equiv CH\xrightarrow[{{H_2}O}]{{H{g^{ + 2}}}}$

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MCQ 2801 Mark

Sum of $x + y =$ ?

A
$2$
✓
$3$
C
$4$
D
$5$

Answer

Correct option: B.

$3$

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MCQ 2811 Mark

$C{H_3} - C \equiv C - C{H_3}\,\xrightarrow[{{\text{(2) B}}{{\text{r}}_2}}]{{{\text{(1)}}{{\text{H}}_2}{\text{ /Pd/CaC}}{{\text{O}}_3}}}\,(X){\kern 1pt} ,\,(X)$ is

A
$(d)-2,3-$ Dibromobutane
B
$(1)-2,3-$ Dibromobutane
✓
$(d, \ell )-2,3-$ Dibromobutane
D
meso $-2,3-$ Dibromobutane

Answer

Correct option: C.

$(d, \ell )-2,3-$ Dibromobutane

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MCQ 2821 Mark

Number of pure $p-$ orbitals in the given molecule hexa $-1, 3-$ dien $-5-$ yne

✓
$8$
B
$6$
C
$4$
D
$10$

Answer

Correct option: A.

$8$

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MCQ 2831 Mark

Which of the following molecule possesses a bond formed by $sp^2-sp$ orbital overlap ?

✓
Butenyne
B
Butadiyne
C
But $-2-$ yne
D
But $-2-$ ene

Answer

Correct option: A.

Butenyne

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MCQ 2841 Mark

Calcium carbide + heavy water $ \to$ ?
The product of the above reaction is

A
$C_2 H_2$
B
$CaD_2$
✓
$Ca(OD)_2$
D
$CD_4$

Answer

Correct option: C.

$Ca(OD)_2$

c
$(c) \,CaC_2 + D_2O \to Ca(OD)_2 + D-C \equiv C - D$

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MCQ 2851 Mark

Order of the bond strength of $C-H$ bonds involving $sp, sp^2$ and $sp^3$ hybridized carbon atoms is

✓
$sp > sp^2 > sp^3$
B
$sp^3 > sp^2 > sp$
C
$sp^2 > sp^3 > sp$
D
$sp^2 > sp > sp^3$

Answer

Correct option: A.

$sp > sp^2 > sp^3$

a
$(a)$ $EN$ value $sp > sp^2 > sp^3$ (more the electronegativity more will be the bond strength)

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MCQ 2861 Mark

Product $(B)$ of the reaction is

$\begin{matrix}
CH-C{{O}_{2}}H \\
\,||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
CH-C{{O}_{2}}H \\
\end{matrix}\xrightarrow[(two\,mole)]{NaOH}(A)\xrightarrow{electrolysis}(B);$

A
$CH_3 -CH_3$
B
$H_2C = CH_2$
✓
$H - C \equiv C - H$
D
$CH_2 = CH -CH =CH_2$

Answer

Correct option: C.

$H - C \equiv C - H$

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MCQ 2871 Mark

Product $(B)$ is

Answer

Correct option: C.

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MCQ 2881 Mark

(image) $X$ can also be formed by

A
$C{H_3} - C{H_2} - C{H_2} - Cl\xrightarrow{{LiAl{H_4}}}$
B
$C{H_3} - C{H_2} - COOH\xrightarrow{{P + HI}}$
✓
$C{H_3} - C \equiv CH\xrightarrow[{{H_2}O}]{{H{g^{ + 2}}}}$
D
All

Answer

Correct option: C.

$C{H_3} - C \equiv CH\xrightarrow[{{H_2}O}]{{H{g^{ + 2}}}}$

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MCQ 2891 Mark

Which of the following reagent is used to distinguish propene and propyne

A
$Br_2,\,CCl_4$
B
Dil. $KMnO_4 /$ $O{H^\Theta }$
C
Conc. $H_2SO_4$
✓
$AgNO_3$ in $NH_4OH$

Answer

Correct option: D.

$AgNO_3$ in $NH_4OH$

d
Propene and propyne can be distinguish by using Ammoniacal silver nitrate test.

Propyne has an acidic hydrogen due to which it readily react with Ammoniacal silver nitrate gives white precipitate while propene does not give any precipitate.

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MCQ 2901 Mark

$CH \equiv CH + CO + {H_2}O\,\xrightarrow{{Ni{{(CO)}_4}}}$ Product,

For this reaction which statement is false

A
The product of reaction is a $\alpha ,$ $\beta -$ unsaturated acid
B
The reaction involves addition of Hydrogen and carboxylic group at $\pi $ bond
C
The product name in this reaction is acrylic acid
✓
The product reacts with ethyl alcohol to give ethyl butanoate

Answer

Correct option: D.

The product reacts with ethyl alcohol to give ethyl butanoate

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MCQ 2911 Mark

Two mole of $HBr$ is added with $CH_3 -C$ $ \equiv $ $CH$ in presence of peroxide to give

A
$CH_3-CH_2-CHBr_2$
✓
$CH_3-CH(Br)-CH_2Br$
C
$CH_3-CBr_2-CH_3$
D
$CH_3 -CH_2Br -CHBr_2$

Answer

Correct option: B.

$CH_3-CH(Br)-CH_2Br$

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MCQ 2921 Mark

$C{H_3} - C \equiv CH\xrightarrow[{(ii)\,\,{H_2}{O_2}/\mathop O\limits^\Theta H}]{{(i)\,\,B{H_3} - THF}}\,(P)$

$C{H_3} - C \equiv CH\xrightarrow[{(ii)\,\,NaB{H_4}}]{{(i)\,\,Hg{{(OAC)}_2}/{H_2}O}}\,(Q)$

Choose the correct option

A
$(P)$ and $(Q)$ are identical in nature
B
$(P)$ and $(Q)$ are geometrical isomer
C
$(P)$ and $(Q)$ are position isomers
✓
$(P)$ and $(Q)$ are functional isomers

Answer

Correct option: D.

$(P)$ and $(Q)$ are functional isomers

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MCQ 2931 Mark

Identify wrong statement

$R - C \equiv C - R\xrightarrow{{Pd/BaS{O_4}}}A$

$R - C \equiv C - R\xrightarrow{{Na/Liq.\,NH_3}}B$

A
$\vec \mu (A) > \vec \mu (B)$
B
Boiling point $(A) >$ boiling point $(B)$
C
Stability $(A) <$ stability $(B)$
✓
Melting point $(A) >$ melting point $(B)$

Answer

Correct option: D.

Melting point $(A) >$ melting point $(B)$

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MCQ 2941 Mark

Which of the following reaction forms aldehyde as a product

✓
$CH \equiv CH\,\xrightarrow[{333\,\,K}]{{H{g^{ + 2}}/{H_3}{O^ \oplus }}}$
B
$C{H_3} - C \equiv CH\,\xrightarrow[{333\,\,K}]{{H{g^{ + 2}}/{H_3}{O^ \oplus }}}$
C
$C{H_3} - C \equiv C - CH\,\xrightarrow[{333\,\,K}]{{H{g^{ + 2}}/{H_3}{O^ \oplus }}}$
D
$A$ and $B$ both

Answer

Correct option: A.

$CH \equiv CH\,\xrightarrow[{333\,\,K}]{{H{g^{ + 2}}/{H_3}{O^ \oplus }}}$

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MCQ 2951 Mark

But $-1-$ yne and But $-2-$ yne can be distinguished by

✓
$(AgNO_3 + NH_4OH)$
B
$Br_2|CCl_4$
C
Baeyer's reagent
D
$HCl$

Answer

Correct option: A.

$(AgNO_3 + NH_4OH)$

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MCQ 2961 Mark

$2-$ Butyne react with $Na$ in liquid Ammonia to form

A
$1-$ butene
B
$Cis$ $-2-$ butene
✓
trans $-2-$ butene
D
$n-$ butane

Answer

Correct option: C.

trans $-2-$ butene

c
When but- $2-$ yne is treated with Na in liquid ammonia, addition of two $\mathrm{H}-$ atoms takes place at the triple bonded carbon atoms in trans manner.

$\begin{aligned}\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{CCH}_{3} \frac{\mathrm{Na}}{\mathrm{Liq.NH}_{3}} \mathrm{CH}_{3}-\mathrm{C}=& \mathrm{C}-\mathrm{CH}_{3} \\& \mathrm{H}\end{aligned}$

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MCQ 2971 Mark

When $CH_3CH_2CH_2CHCl_2$ is treated with $2\, gram$ equivalent $NaNH_2$, the product formed is

✓
$C{H_3}C{H_2}C \equiv CH$
B
$C{H_3}C{H_2}-CH = C{H_2}$
C
D

Answer

Correct option: A.

$C{H_3}C{H_2}C \equiv CH$

a
$CH_3-CH_2-CH_2-CHCl_2$ $\xrightarrow{{NaN{H_2}}}C{H_3} - C{H_2} - C \equiv CH$

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MCQ 2981 Mark

Which of the following compound does not react with $Na$ ?

A
$CH_3OH$
B
$C{H_3} - C \equiv CH$
C
$Ph-OH$
✓
cyclohexane

Answer

Correct option: D.

cyclohexane

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MCQ 2991 Mark

$C{H_3} - C \equiv CH\xrightarrow{{Na}}X\xrightarrow{{C{H_3} - Cl}}Y$ ,

$Y$ is

A
$C{H_3} - C{H_2} - C \equiv CH$
✓
$C{H_3} - C \equiv C - C{H_3}$
C
$C{H_3} - C{H_2} - CH = C{H_2}$
D
$C{H_3} - CH = CH - C{H_3}$

Answer

Correct option: B.

$C{H_3} - C \equiv C - C{H_3}$

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MCQ 3001 Mark

When $23\, g$ $Na$ reacts with $1\, mole$ of propyne then how many mole of $H_2$ gas will be released......$mole$

A
$1$
✓
$0.5$
C
$1.5$
D
$2$

Answer

Correct option: B.

$0.5$

b
$C{{H}_{3}}-C\equiv CH+\underset{\begin{smallmatrix}
23\,gm \\
\left( 1\,mole \right)
\end{smallmatrix}}{\mathop{Na}}\,\longrightarrow C{{H}_{3}}\equiv {{C}^{\Theta }}N{{a}^{\oplus }}+\underset{\left( 1/2\,mole \right)}{\mathop{1/2{{H}_{2}}}}\,$

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MCQ 3011 Mark

Which of the following are not aromatic

A
Benzene
B
Cyclo-octatetrarenyl dianion
C
Tropyllium cation
✓
Cyclopentadienyl cation

Answer

Correct option: D.

Cyclopentadienyl cation

d
It’s obvious.

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MCQ 3021 Mark

Cyclopentadienyl anion is

✓
Aromatic
B
Non-aromatic
C
Non-planar
D
Aliphatic

Answer

Correct option: A.

Aromatic

a
It’s obvious.

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MCQ 3031 Mark

Which gives monosubstituted product

A
$o$- dinitrobenzene
✓
$m$- dinitrobenzene
C
$p$- dinitrobenzene
D
Nitrobenzene

Answer

Correct option: B.

$m$- dinitrobenzene

b
(b) gives only monosubstitution product as $ - N{O_2}$ group is meta directing and only one $m$-position is possible in $m$- dinitrobenzene.

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MCQ 3041 Mark

The presence of the chlorine atom on benzene ring makes the second substituent enter at a position

A
ortho
B
meta
C
para
✓
ortho-para

Answer

Correct option: D.

ortho-para

d
(d)Chlorine atom is orth-para directing group.

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MCQ 3051 Mark

In electrophilic substitution reaction nitrobenzene is

A
Para-directing
B
Ortho-directing
✓
Meta-directing
D
Not reactive and does not undergo any substitution

Answer

Correct option: C.

Meta-directing

c
Nitrobenzene is meta-directing for an electrophilic substitution reaction since it has an electron-withdrawing group (i.e $NO _2$ ). There is less electron density at ortho- and para- position and more electron density at meta- position. That's why it is meta directing.

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MCQ 3061 Mark

The most common type of reaction in aromatic compounds is

A
Elimination reaction
B
Addition reaction
✓
Electrophilic substitution reaction
D
Rearrangement reaction

Answer

Correct option: C.

Electrophilic substitution reaction

c
Aromatic compounds or arenes undergo substitution reactions, in which the aromatic hydrogen is replaced with an electrophile, hence their reactions proceed via electrophilic substitution.

Arenes contain double bonds just like alkenes but they do not undergo electrophilic addition because these would result to their loss of ring aromaticity.

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MCQ 3071 Mark

The function of $AlC{l_3}$ in Friedel-Craft’s reaction is

A
To absorb $HCl$
B
To absorb water
C
To produce nucleophile
✓
To produce electrophile

Answer

Correct option: D.

To produce electrophile

d
The function of $AlCl _3$ in Friedel-Crafts reaction, is to produce electrophile which later attack on benzene.

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MCQ 3081 Mark

Which of the following can’t be used in Friedal Craft’s reactions

A
$FeC{l_3}$
B
$FeB{r_2}$
C
$AlC{l_3}$
✓
$NaCl$

Answer

Correct option: D.

$NaCl$

d
(d)All cations are expected to act as Lewis acid since they are electron deficient in nature. However cation such as $N{a^ + },\;{K^ + }$ etc. (Inert gas configuration) have a very little tendency to accept electrons. Therefore they do not acts as lewis acids in friedel Craft’s reaction.

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MCQ 3091 Mark

The nitration of a compound is due to the

A
$N{O_2}$
B
$N{O_3}$
C
$NO$
✓
$NO_2^ + $

Answer

Correct option: D.

$NO_2^ + $

d
(d) The process of nitration takes place as below

$HON{O_2} + 2{H_2}S{O_4}$ $ \rightleftharpoons $ ${H_3}{O^ + } + 2HSO_4^ - + \mathop {NO_2^ + }\limits_{({\rm{nitronium ion}})} $

The electrophile responsible for nitration is $NO_2^ + $ ion.

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MCQ 3101 Mark

The product formed when acetylene is passed through red hot tube is

✓
Benzene
B
Cyclohexane
C
Neoprene
D
Ethane

Answer

Correct option: A.

Benzene

a
(a)

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MCQ 3111 Mark

Which of the following pairs has the same bond angle

A
Ethane and ethylene
B
Ethylene and acetylene
✓
Ethylene and benzene
D
Acetylene and benzene

Answer

Correct option: C.

Ethylene and benzene

c
(c) Ethylene and Benzene
$120^°$ $120^°$
$s{p^2}$ $s{p^2}$

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MCQ 3121 Mark

Benzene is the polymer of

A
Methane
B
Ethane
C
Ethylene
✓
Ethyne

Answer

Correct option: D.

Ethyne

d
(d)

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MCQ 3131 Mark

The compound formed as a result of potassium permanganate oxidation of ethylbenzene is

✓
Benzoic acid
B
Benzyl alcohol
C
Benzophenone
D
Acetophenone

Answer

Correct option: A.

Benzoic acid

a
The compound formed as a result of oxidation of ethyl benzene by alkaline $KMnO _4$ is benzoic acid.

Other reagents that can be used are acidified potassium dichromate or dilute nitric acid.

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MCQ 3141 Mark

The function of anhydrous $AlC{l_3}$ in the Friedel-Craft's reaction is to

A
Absorb water
B
Absorb $HCl$
✓
To produce electrophile
D
To produce nucleophile

Answer

Correct option: C.

To produce electrophile

c
The function of $AlCl _3$ in Friedel-Crafts reaction, is to produce electrophile which later attack on benzene.

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MCQ 3151 Mark

Acylation process is preferred than direct alkylation because (by the Friedel-Craft's reaction)

A
In alkylation, a poisonous gas is evolved
B
In alkylation, large amount of heat is evolved
✓
In alkylation, polyalkylated product is formed
D
Alkylation is very costly

Answer

Correct option: C.

In alkylation, polyalkylated product is formed

c
When benzene is alkylated, along with mono alkyl benzene, polyalkylation products are also obtained. Hence, instead of direct alkylation, acylation is preferred. This is followed by reduction of carbonyl group to methylene group.

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MCQ 3161 Mark

The reaction of benzene with chlorine in the presence of iron gives

A
Benzene hexachloride
✓
Chlorobenzene
C
Benzyl chloride
D
Benzoyl chloride

Answer

Correct option: B.

Chlorobenzene

b
(b)

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MCQ 3171 Mark

Benzene on treatment with a mixture of conc. $HN{O_3}$ and conc. ${H_2}S{O_4}$ at ${100\,^o}C$ gives

A
Nitrobenzene
✓
$m-$dinitrobenzene
C
$p-$dinitrobenzene
D
$o-$dinitrobenzene

Answer

Correct option: B.

$m-$dinitrobenzene

b
(b)

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MCQ 3181 Mark

What is the end product which is obtained on the nitration of toluene

A
$o-$nitrotoluene
B
$p-$nitrotoluene
C
$2, 4-$dinitrotoluene
✓
$2, 4, 6-$trinitrotoluene

Answer

Correct option: D.

$2, 4, 6-$trinitrotoluene

d
(d)

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MCQ 3191 Mark

Which of the following processes is reversible

A
Halogenation
✓
Sulphonation
C
Nitration
D
None

Answer

Correct option: B.

Sulphonation

b
(b)

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MCQ 3201 Mark

The attacking (electrophilic) species in sulphonation of benzene is

A
$S{O_2}$
✓
$S{O_3}$
C
$SO_4^{2 - }$
D
$HSO_3^ - $

Answer

Correct option: B.

$S{O_3}$

b
Sulphur trioxide $SO _3$ is active species in sulphonation of benzene.

$SO _3$ acts as an electrophile and accepts a pair of $pi$ electrons from benzene.

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MCQ 3211 Mark

Which xylene is most easily sulphonated

A
Ortho
B
Para
✓
Meta
D
All at the same rate

Answer

Correct option: C.

Meta

c
(c) $m-$ xylene is most easily sulphonated because $O$ and $P$ both positions are free with respect to methyl group.

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MCQ 3221 Mark

Toluene on oxidation with dilute $HN{O_3}$ and alkaline $KMn{O_4}$ gives

A
Benzaldehyde
B
Phenol
C
Nitrotoluene
✓
Benzoic acid

Answer

Correct option: D.

Benzoic acid

d
(d)

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MCQ 3231 Mark

Benzene vapour mixed with air when passed over ${V_2}{O_5}$ catalyst at $775\,K$ gives

A
Glyoxal
B
Oxalic acid
✓
Maleic anhydride
D
Fumaric acid

Answer

Correct option: C.

Maleic anhydride

c
(c)

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MCQ 3241 Mark

Most common reactions of benzene (aromatic hydrocarbon) and its derivatives are

A
Electrophilic addition reactions
✓
Electrophilic substitution reactions
C
Nucleophilic addition reactions
D
Nucleophilic substitution reactions

Answer

Correct option: B.

Electrophilic substitution reactions

b
Benzene and it's derivatives is much more stable than expected. The extra stability means that benzene will less readily undergo addition reactions. The more loosely held electrons are open to attack by electrophiles. Hence, the characteristic reaction of benzene is electrophilic substitution reaction.

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MCQ 3251 Mark

Which is most readily nitrated

A
Benzene
✓
Phenol
C
Aniline
D
Nitrobenzene

Answer

Correct option: B.

Phenol

b
(b)Phenol is most easily nitrated.

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MCQ 3261 Mark

$o, p-$ directing groups are mostly

✓
Activating groups
B
Deactivating groups
C
Neutral groups
D
None of these

Answer

Correct option: A.

Activating groups

a
Most $o,p$-directing groups are Activating Group. If electrophilic aromatic substitution of a monosubstituted benzene is faster than that of benzene under identical conditions, the substituent in the monosubstituted benzene is called an Activating Group.

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MCQ 3271 Mark

Which of the following would be least reactive towards bromine

✓
Nitrobenzene
B
Phenol
C
Anisole
D
Chlorobenzene

Answer

Correct option: A.

Nitrobenzene

a
(a) Nitrobenzene is least reactive towards bromine because of presence of $ - N{O_2}$ group decreases electron density at $o$ and $p$ positions and hence attack of electrophile on the benzene nucleus is difficult because $+ ve$ charge on $o$ and $p$ position repel the incoming electrophile.

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MCQ 3281 Mark

Amongst the following, the compound that is nitrated with difficulty is

A
Benzene
✓
Nitrobenzene
C
Toluene
D
Phenol

Answer

Correct option: B.

Nitrobenzene

b
Nitrogen of nitro benzene is difficult as it contain electron with drawing group, making compound electron elements.

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MCQ 3291 Mark

$(i)$ Chlorobenzene and $(ii)$ benzene hexachloride are obtained from benzene by the reaction of chlorine, in the presence of

A
$(i)$ Direct sunlight and $(ii)$ anhydrous $AlC{l_3}$
B
$(i) $ Sodium hydroxide and $(ii)$ sulphuric acid
C
$(i)$ Ultraviolet light and $(ii)$ anhydrous $FeC{l_3}$
✓
$(i)$ Anhydrous $AlC{l_3}$ and $(ii)$ direct sunlight

Answer

Correct option: D.

$(i)$ Anhydrous $AlC{l_3}$ and $(ii)$ direct sunlight

d
(d)

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MCQ 3301 Mark

Nitration of benzene is a

✓
Electrophilic displacement
B
Electrophilic addition
C
Nucleophilic addition
D
Nucleophilic displacement

Answer

Correct option: A.

Electrophilic displacement

a
Nitration of benzene involves the formation of a very powerful electrophile, the nitronium ion, which is linear. This occurs following the interaction of two strong acids, sulfuric and nitric acid. Sulfuric acid is the stronger and it protonates the nitric acid on the $OH$ group so that a molecule of water can leave. Benzene attacks the positively charged nitrogen atom of the electrophile, where one of the $N = O$ bonds is broken at the same time. This is followed by rapid loss of a proton to regenerate the aromaticity.

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MCQ 3311 Mark

Benzene shows

A
Substitution
B
Addition
C
Oxidation
✓
All of these

Answer

Correct option: D.

All of these

d
There are delocalised electrons above and below the plane of the ring. The presence of the delocalised electrons makes benzene particularly stable.

Benzene resists addition reactions because that would involve breaking the delocalisation and losing that stability.

An alkylbenzene is simply a benzene ring with an alkyl group attached to it. ... Alkyl groups are usually fairly resistant to oxidation. However, when they are attached to a benzene ring, they are easily oxidised by an alkaline solution of potassium manganate($VII$) (potassium permanganate).

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MCQ 3321 Mark

Benzene can be obtained in the reaction

A
Ethene $+ 1, 3-$butadiene
✓
Trimerisation of ethyne
C
Reduction of $PhCHO$
D
All of these

Answer

Correct option: B.

Trimerisation of ethyne

b
(b) Benzene can be obtained by polymerisation of acetylene.

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MCQ 3331 Mark

Thiophene and benzene are separated by

A
Sulphonation of thiophene
✓
Sulphonation of benzene
C
Nitration of thiophene
D
Nitration of benzene

Answer

Correct option: B.

Sulphonation of benzene

b
Probably the most convenient method is to use the fact that thiophene is highly reactive toward sulfonation.

Shaking a mixture of benzene and thiophene with sulfuric acid at room temperature causes sulfonation of the thiophene but leaves the benzene untouched.

The thiophene sulfonic acid dissolves in the sulfuric acid layer, which you can separate.

You can then wash, dry, and distill the benzene in the usual way.

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MCQ 3341 Mark

Which of the following is a hydrocarbon

A
Urea
✓
Benzene
C
Ammonium cyanate
D
Phenol

Answer

Correct option: B.

Benzene

b
(b) Benzene ${C_6}{H_6}$ is made up of hydrogen and carbon only.

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MCQ 3351 Mark

Aromatic compounds burn with sooty flame because

A
They have a ring structure of carbon atoms
B
They have a relatively high percentage of hydrogen
✓
They have a relatively high percentage of carbon
D
They resist reaction with oxygen of air

Answer

Correct option: C.

They have a relatively high percentage of carbon

c
(c)They have a relatively high percentage of carbon

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MCQ 3361 Mark

Among the following compound which one is planar in shape

A
Methane
B
Acetylene
✓
Benzene
D
Isobutane

Answer

Correct option: C.

Benzene

c
(c) All $6$ carbons of Benzene are $s{p^2}$-hybridised so it is planar.

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MCQ 3371 Mark

Methyl group attached to benzene can be oxidised to carboxyl group by reacting with

A
$F{e_2}{O_3}$
B
$AgN{O_3}$
✓
$KMn{O_4}$
D
$C{r_2}{O_3}$

Answer

Correct option: C.

$KMn{O_4}$

c
(c)

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MCQ 3381 Mark

How it is widely used

A
Insecticide
B
Drug
✓
Explosive
D
Dye

Answer

Correct option: C.

Explosive

c
(c) $2,4,6-$Trinitro toluene $(TNT)$ is used as explosive.

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MCQ 3391 Mark

The compound ‘$A$’ when treated with $HN{O_3}$ (in presence of ${H_2}S{O_4}$) gives compound ‘$B$’ which is then reduced with $Sn$ and $HCl$ to aniline. The compound ‘$A$’ is

A
Toulene
✓
Benzene
C
Ethane
D
Acetamide

Answer

Correct option: B.

Benzene

b
(b)

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MCQ 3401 Mark

The compound used as an explosive is

A
$2,4, 6$ -tribromoaniline
B
$1,3, 5-$ trinitrobenzene
C
$2,4, 6-$ trichlorotoluene
✓
$2,4, 6-$ trinitrotoluene

Answer

Correct option: D.

$2,4, 6-$ trinitrotoluene

d
(d) $TNT$ is used as an explosive.

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MCQ 3411 Mark

Adding of $C{l_2}$ to benzene in the presence of $AlC{l_3}$ is an example of

A
Addition
B
Halogenation
C
Elimination
✓
Substitution

Answer

Correct option: D.

Substitution

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MCQ 3421 Mark

What happens when naphthalene balls are put inside kerosene

A
Precipitates
B
Dissolves upon heating
✓
Dissolves easily
D
Does not dissolve

Answer

Correct option: C.

Dissolves easily

c
compounds dissolves in polar solvents non polar or covalent compounds dissolved in non polar solvents.

Here, naphthalene and kerosene are polar compounds.

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MCQ 3431 Mark

Three fused benzene rings are found in

A
Naphthalene
✓
Anthracene
C
Phenanthroline
D
Triphenyl methane

Answer

Correct option: B.

Anthracene

b
Anthracene is a solid polycyclic aromatic hydrocarbon ($PAH$) of formula $C _{14} H _{10}$ consisting of three fused benzene rings. It is a component of coal tar.

Anthracene is used in the production of the red dye alizarin and other dyes.

Anthracene is colorless but exhibits a blue $(400-500\, nm$ peak) fluorescence under ultraviolet radiation

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MCQ 3441 Mark

Product obtained after nitration of nitrobenzene is

A
$TNT$
✓
$1, 3-$dinitrobenzene
C
Picric acid
D
$1, 4-$dinitrobenzene

Answer

Correct option: B.

$1, 3-$dinitrobenzene

b
(b)

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MCQ 3451 Mark

After ozonolysis of benzene (not hydrolysis), the product is

✓
Benzene triozonide
B
Glyoxal
C
Ethanediol
D
All of them

Answer

Correct option: A.

Benzene triozonide

a
Ozonolysis is the cleavage of an alkene or alkyne with ozone to form organic compounds in which the multiple carbon-carbon bond has been replaced by a double bond to oxygen. The ozonolysis of benzene forms Glyoxal through the formation of benzene Triozonide as an intermediate.

Therefore in here is no hydrolysis take place so benzene Trioznide is seems as a product.

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MCQ 3461 Mark

The compound ‘$A$’ having formula ${C_8}{H_{10}}$ (aromatic) which gives $1$ mononitro substitute and $3$ nitrosubstitute compound is

A
$m-$Xylene
✓
$p-$Xylene
C
$o-$Xylene
D
Ethyl benzene

Answer

Correct option: B.

$p-$Xylene

b
From above reaction we find best appropriate option is $B$.

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MCQ 3471 Mark

Benzene is obtained from

✓
Coaltar
B
Plant
C
Animal
D
Charcoal

Answer

Correct option: A.

Coaltar

a
Benzene was first discovered by the English scientist Michael Faraday in $1825$ in illuminating gas. In $1834$ German chemist Eilhardt Mitscherlich heated benzoic acid with lime and produced benzene. In $1845$ German chemist A.W. von Hofmann isolated benzene from coal tar.

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MCQ 3481 Mark

The ‘middle oil’ fraction of coaltar distillation contains

A
Benzene
B
Anthracene
✓
Naphthalene
D
Xylene

Answer

Correct option: C.

Naphthalene

c
Aromatic hydrocarbons are obtained by fractional distillation of coal tar. The first fraction (crude light oil) mainly contains benzene, toluene and xylene. The second fraction (middle oil) contains naphthalene, while the next fraction (green oil) contains mainly anthracene and phenanthrene.

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MCQ 3491 Mark

Lindane can be obtained by reaction of benzene with

A
$C{H_3}Cl$ / anhy.$AlC{l_3}$
✓
$C{l_2}$ / sunlight
C
${C_2}{H_5}I$ / anhy.$AlC{l_3}$
D
$C{H_3}COCl / AlC{l_3}$

Answer

Correct option: B.

$C{l_2}$ / sunlight

b
(b)

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MCQ 3501 Mark

Which of the following oil is obtained from benzene after fractional distillation of coal tar

✓
Light oil
B
Heavy oil
C
Middle oil
D
Anthracene oil

Answer

Correct option: A.

Light oil

a
(a)Benzene on fractional distillation gives light oil [It is lighter than water and hence called as light oil]

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MCQ 3511 Mark

Decreasing order of $C-C$ bond length is

$I.$ ${C_2}{H_4}$ $II.$ ${C_2}{H_2}$

$III.$ ${C_6}{H_6}$ $IV.$ ${C_2}{H_6}$

✓
$IV > III > I > II$
B
$I > II > IV > III$
C
$II > I > IV > III$
D
$IV > I > III > II$

Answer

Correct option: A.

$IV > III > I > II$

a
(a) Bond length $ \propto \frac{1}{{{\rm{Bond order}}}}$

Bond order = $\frac{{{\rm{Bonding -- antibonding electron}}}}{{\rm{2}}}$

Bond order is highest for ${C_2}{H_6}$ so it has minimum bond strength.

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MCQ 3521 Mark

Benzene can be obtained by heating either benzoic acid with $X$ or phenol with $Y$. $X$ and $Y$ are respectively

A
Zinc dust and soda lime
✓
Soda lime and zinc dust
C
Zinc dust and sodium hydroxide
D
Soda lime and copper

Answer

Correct option: B.

Soda lime and zinc dust

b
(b) ${C_6}{H_5}COOH + \mathop {NaOH}\limits_{{\text{(x)}}} \to {C_6}{H_5}COONa + {H_2}O$ $\xrightarrow{{NaOH}}{C_6}{H_6} + N{a_2}C{O_3}$

${C_6}{H_5}OH + \mathop {Zn}\limits_{{\text{(y)}}} \xrightarrow{{{\text{distill}}}}{C_6}{H_6} + ZnO$

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MCQ 3531 Mark

When toluene is treated with $KMn{O_4}$, what is produced

A
Benzene
B
Chlorobenzene
C
Benzaldehyde
✓
Benzoic acid

Answer

Correct option: D.

Benzoic acid

d
(d)

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MCQ 3541 Mark

In presence of light & heat toluene chlorinated & react with aqueous $NaOH$ to give

A
$o-$Cresol
B
$p-$Cresol
C
Mixture of $o-$ Cresol & $p-$Cresol
✓
Benzoic acid

Answer

Correct option: D.

Benzoic acid

d
(d)

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MCQ 3551 Mark

Which of the following is Friedel-Craft's reaction

A
${C_6}{H_6} + FeC{l_3} + C{l_2} \to {C_6}{H_5}Cl$
B
${C_6}{H_5}CHO + C{H_3}CHO + KOH \to {C_6}{H_5}CH = CH - CHO$
✓
${C_6}{H_6} + C{H_3}COCl + AlC{l_3} \to \mathop {\mathop {{C_6}{H_5} - C - C{H_3}}\limits^{\,\,\,\,||} }\limits^{\,\,\,O} $
D
${C_6}{H_5}OH + CHC{l_3} + KOH\xrightarrow{{}}{\text{Salicylaldehyde}}$

Answer

Correct option: C.

${C_6}{H_6} + C{H_3}COCl + AlC{l_3} \to \mathop {\mathop {{C_6}{H_5} - C - C{H_3}}\limits^{\,\,\,\,||} }\limits^{\,\,\,O} $

c
(c) Friedel-craft's reaction

$\mathop {C{H_3}COCl}\limits_{{\text{Acetyl chloride}}} + \mathop {{C_6}{H_6}}\limits_{{\text{Benzene}}} \xrightarrow{{{\text{anhydrous }}AlC{l_3}}}\mathop {C{H_3}CO{C_6}{H_5}}\limits_{{\text{Acetophenone}}} + HCl$

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MCQ 3561 Mark

Which one of the following reactions is most suitable for the preparation of $n-$ propyl benzene

A
Friedel-Craft's reaction
B
Wurtz reaction
✓
Wurtz-Fittig reaction
D
Grignard reaction

Answer

Correct option: C.

Wurtz-Fittig reaction

c
(c)

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MCQ 3571 Mark

Naphthalene is a/an

A
Ionic solid
B
Covalent solid
C
Metallic solid
✓
Molecular solid

Answer

Correct option: D.

Molecular solid

d
(d) Naphthalene is a molecular solid. If the crystals contains only individuals atoms; as in solid argon or krypton or if they are composed of non polar molecules as in naphthalene, the only attraction between the molecules are the London forces.

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MCQ 3581 Mark

Which of the following is not aromatic

A
Benzene
B
Naphthalene
C
Pyridine
✓
$1,3,5- $heptatriene

Answer

Correct option: D.

$1,3,5- $heptatriene

d
(d) A compound is said to be aromatic if it is planar and there is complete delocalization of $\pi $ electrons, which is only possilble if it is a conjugated cyclic system and number of electrons used in delocalization is $(4n + 2)$. $1, 3, 5- $heptatriene is not an aromatic compound because complete delocalization of $\pi $ electrons, is not possible in it.

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MCQ 3591 Mark

A group which deactivates the benzene ring towards electrophilic substitution but which directs the incoming group principally to the $o-$ and $p-$ positions is

A
$ - N{H_2}$
✓
$ - Cl$
C
$ - N{O_2}$
D
$ - {C_2}{H_5}$

Answer

Correct option: B.

$ - Cl$

b
(b) Electron accepting groups which make the substitution difficult are known of deactivating groups. the group or substituent already present on the ring also decides the position of incoming group.

ortho and para directing groups are as follow

$ - C{H_3},{C_2}{H_5}( - R), - N{H_2}, - OH$, halogens, $(Cl,\,Br,\,I)$

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MCQ 3601 Mark

Which order is correct for the decreasing reactivity to ring monobromination of the following compounds

$\begin{array}{l}{C_6}{H_5}C{H_3},\\\,\,\,\,\,\,\,\,\,\,{\rm{I}}\end{array}$$\begin{array}{l}{C_6}{H_5}COOH,\\\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{II}}\end{array}$$\begin{array}{l}{C_6}{H_6}\\\,\,\,\,{\rm{III}}\end{array}$$\begin{array}{l}{C_6}{H_5}N{O_2}\\\,\,\,\,\,\,\,\,\,\,{\rm{IV}}\end{array}$

A
$I > II > III > IV$
✓
$I > III > II > I$
C
$II > III > IV > I$
D
$III > I > II > IV$

Answer

Correct option: B.

$I > III > II > I$

b
(b)

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MCQ 3611 Mark

Benzene is obtained by

A
Substitution of three acetylene molecules
B
Addition of three ${C_2}{H_2}$ molecules
✓
Polymerisation of three ${C_2}{H_2}$ molecules
D
Condensation of three ${C_2}{H_2}$ molecules

Answer

Correct option: C.

Polymerisation of three ${C_2}{H_2}$ molecules

c
(c) Polymerisation

$3CH \equiv CH\mathop {\xrightarrow{{{\text{heat}}}}}\limits_{Cu,\,{{500}\,^o}C} $

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MCQ 3621 Mark

In presence of light toluene on reaction with chlorine gives

A
Benzoyl chloride
B
Ortho chlorotoluene
C
Para chloro toluene
✓
Benzyl chloride

Answer

Correct option: D.

Benzyl chloride

d
(d) Sidechain chlorination and bromination is favoured by high temperature, light and in absence of halogen carrie

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MCQ 3631 Mark

Which of the following is an electrophile

A
${H_2}O$
B
$N{H_3}$
✓
$AlC{l_3}$
D
${C_2}{H_5}N{H_2}$

Answer

Correct option: C.

$AlC{l_3}$

c
$AlCl_3$ is an electron deficient compound.

Hence, act as an electrophile.

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MCQ 3641 Mark

In reaction ${C_6}{H_5}C{H_3}\xrightarrow[{{\text{Oxidation}}}]{}A\xrightarrow[{NaOH}]{}B\xrightarrow{{{\text{Sodalime}}}}C$ Then $C$ is

✓
${C_6}{H_6}$
B
${C_6}{H_5}OH$
C
${C_6}{H_5}COON\mathop a\limits^ + $
D
${C_6}{H_5}ONa$

Answer

Correct option: A.

${C_6}{H_6}$

a
(a) ${C_6}{H_5}C{H_3}\xrightarrow{{[O]}}\mathop {{C_6}{H_5}COOH}\limits_{[A]} \xrightarrow{{NaOH}}$
$\mathop {{C_6}{H_5}COONa}\limits_{[B]} \xrightarrow{{NaOH/CaO}}\mathop {{C_6}{H_6}}\limits_{[C]} $

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MCQ 3651 Mark

Which of the following will be easily nitrated

✓
B
C
$C{H_3}N{O_2}$
D
${C_6}{H_5}N{O_2}$

Answer

Correct option: A.

a
(a) The presence of an electron-releasing groups ($+I$ group) e.g., $ - C{H_3}, - OH, - N{H_2}$ etc makes the process of nitration easier. So ${C_6}{H_3}C{H_3}$ will be easily nitrated.

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MCQ 3661 Mark

Chlorination of benzene is not possible in the following reaction

A
${C_6}{H_6} + C{l_2}\xrightarrow{{FeC{l_3}}}$
✓
${C_6}{H_6} + HOCl\xrightarrow{{{H^ + }}}$
C
${C_6}{H_6} + I - Cl\xrightarrow{{ZnC{l_2}}}$
D
${C_6}{H_6} + C{l_2}\xrightarrow{{AlC{l_3}}}$

Answer

Correct option: B.

${C_6}{H_6} + HOCl\xrightarrow{{{H^ + }}}$

b
(b) Reaction is called Gattermann-Koch synthesis, which is carried by catalyst $AlC{l_3}$.

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MCQ 3671 Mark

Which of the following is non-aromatic ?

A
Pyrrole
B
Thiophene
C
Furan
✓
Pyran

Answer

Correct option: D.

Pyran

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MCQ 3681 Mark

Identify anti aromatic compound ?

Answer

Correct option: B.

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MCQ 3691 Mark

product is ?

Answer

Correct option: D.

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MCQ 3701 Mark

Decide the correct order of reactivity of following compounds towards halogenation with $(Cl_2 + AlCl_3)$

✓
$I$ > $II$ > $III$ > $IV$
B
$II$ > $III$ > $IV$ > $I$
C
$III$ > $II$ > $IV$ > $I$
D
$II$ > $III$ > $I$ > $IV$

Answer

Correct option: A.

$I$ > $II$ > $III$ > $IV$

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MCQ 3711 Mark

How many $\pi$ electron are there in the following species :

A
$2$
B
$4$
✓
$6$
D
$8$

Answer

Correct option: C.

$6$

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MCQ 3721 Mark

Number of $\pi$ electrons present in naphthalene is :

A
$2$
B
$4$
✓
$10$
D
$14$

Answer

Correct option: C.

$10$

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MCQ 3731 Mark

Which of the following is not the property of benzene:

A
Characteristic smell
B
Inflammable
✓
Unsaturation
D
Colourless

Answer

Correct option: C.

Unsaturation

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MCQ 3741 Mark

Benzene undergoes substitution reaction more easily than addition because:

A
It has a cyclic structure
B
It has three double bonds
C
It has six hydrogen atoms
✓
Of resonance

Answer

Correct option: D.

Of resonance

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MCQ 3751 Mark

Find odd compound out :

A
Lindane
B
Gammexane
C
$666$
✓
$HCB$

Answer

Correct option: D.

$HCB$

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MCQ 3761 Mark

Which of the following reagents and conditions convert benzene to chloro-benzene :

A
$Cl_2,$ sunlight, heat
B
$HCl,$ heat
C
$HCl,$ sunlight, heat
✓
$Cl_2, AlCl_3,$ cold

Answer

Correct option: D.

$Cl_2, AlCl_3,$ cold

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MCQ 3771 Mark

Which order is correct for the decreasing reactivity to ring monobromination of the following compounds :

$(I) \,C_6H_5CH_3$

$(II)\, C_6H_5COOH$

$(III)\, C_6H_6$

$(IV) \,C_6H_5NO_2$

A
$I > II > III > IV$
✓
$I > III > II > IV$
C
$II > III > IV > I$
D
$III > I > II > IV$

Answer

Correct option: B.

$I > III > II > IV$

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MCQ 3781 Mark

Benzene on treatment with a mixture of conc. $HNO_3$ and conc. $H_2SO_4$ at $90^o C$ gives :

A
Nitrobenzene
✓
$m-$ Dinitrobenzene
C
$p-$ Dinitrobenzene
D
$o-$ Dinitrobenzene

Answer

Correct option: B.

$m-$ Dinitrobenzene

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MCQ 3791 Mark

Which of the following structures correspond to the product expected, when excess of $C_6H_6$ reacts with $CH_2Cl_2$ in presence of anhydrous $AlCl_3$ :

Answer

Correct option: D.

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MCQ 3801 Mark

Which of the following group is divalent :

A
Benzoyl
B
Benzyl
✓
Benzal
D
$p-$ Tolyl

Answer

Correct option: C.

Benzal

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MCQ 3811 Mark

$C_6H_6 + A \xrightarrow{{AlC{l_3}}} C_6H_5CONH_2$

$A$ in the above reaction is:

A
$NH_2CONH_2$
✓
$ClCONH_2$
C
$CH_3CONH_2$
D
$CH_2(Cl)CONH_2$

Answer

Correct option: B.

$ClCONH_2$

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MCQ 3821 Mark

When benzene is heated with acetic anhydride in the presence of anhydrous aluminium chloride at $80^o C,$ the product formed is :

A
Benzoic acid
B
Benzophenone
✓
Acetophenone
D
Ethyl phenyl ketone

Answer

Correct option: C.

Acetophenone

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MCQ 3831 Mark

${C_6}{H_6}\mathop {\xrightarrow{{C{H_3}COCl}}}\limits_{AlC{l_3}} A\mathop {\xrightarrow{{Zn - Hg}}}\limits_{HCl} B$

The end product in the above sequence is :

A
Toluene
✓
Ethyl benzene
C
Both the above
D
None

Answer

Correct option: B.

Ethyl benzene

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MCQ 3841 Mark

The species responsible for nitration and sulphonation by nitric acid conc. $H_2SO_4$ and fuming $H_2SO_4$ are :

A
$NO_2$ and $SO_3$
✓
$NO_2^+$ and $SO_3$
C
$NO^+$ and $SO_2$
D
$NO_2$ and $SO_2$

Answer

Correct option: B.

$NO_2^+$ and $SO_3$

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MCQ 3851 Mark

Reaction of $SO_3$ is easier in :

A
Benzene
✓
Toluene
C
Nitrobenzene
D
chlorobenzene

Answer

Correct option: B.

Toluene

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MCQ 3861 Mark

If the mixture of the following four aromatic compounds on oxidation by strong oxidising agent gives :

A
Mixture of $C_6H_5CH_2OH + C_6H_5COOH$
B
Mixture of $C_6H_5CHO + C_6H_5COOH$
✓
Only $C_6H_5COOH$
D
None of the above

Answer

Correct option: C.

Only $C_6H_5COOH$

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MCQ 3871 Mark

Methyl group attached to benzene can be oxidised to carboxyl group by reacting with :

A
$Fe_2O_3$
B
$AgNO_3$
✓
$KMnO_4$
D
$CrO_3$

Answer

Correct option: C.

$KMnO_4$

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MCQ 3881 Mark

The reaction of benzene with $CO$ and $HCl$ in the presence of anhydrous $AlCl_3$ gives :

A
Chlorobenzene
B
Toluene
C
Benzyl chloride
✓
Benzaldehyde

Answer

Correct option: D.

Benzaldehyde

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MCQ 3891 Mark

The number of benzylic hydrogen atoms in ethylbenzene is :

A
$3$
B
$5$
✓
$2$
D
$7$

Answer

Correct option: C.

$2$

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MCQ 3901 Mark

$X\xrightarrow{{C{l_2}}}$ Benzotrichloride $\xrightarrow{{Hydrolysis}}Y$

$X$ and $Y$ respectively are :

A
Benzene, Benzaldehyde
B
Toluene, Benzaldehyde
✓
Toluene, Benzoic acid
D
Benzene, Benzoic acid

Answer

Correct option: C.

Toluene, Benzoic acid

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MCQ 3911 Mark

Product obtained when benzoyl acetic acid is heated with soda-lime is :

Answer

Correct option: A.

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MCQ 3921 Mark

Etard reaction in the following is :

✓
Oxidation of toluene to benzaldehyde by chromylchloride
B
Oxidation of toluene to benzaldehyde by alkaline $KMnO_4$
C
Dry distillation of calcium benzoate
D
Reaction of benzene with $Cl_2$ in the presence of $UV$ light

Answer

Correct option: A.

Oxidation of toluene to benzaldehyde by chromylchloride

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MCQ 3931 Mark

The highest yield of $m-$ product is possible by the electrophilic substitution of the following :

A
$C_6H_5CH_3$
B
$C_6H_5CH_2COOC_2H_5$
C
$C_6H_5CH(COOC_2H_5)_2$
✓
$C_6H_5C(COOC_2H_5)_3$

Answer

Correct option: D.

$C_6H_5C(COOC_2H_5)_3$

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MCQ 3941 Mark

Which of the following is/are produced when a mixture of benzene vapour and oxygen is passed over $V_2O_5$ catalyst at $775\, K$ ?

A
Oxalic acid
B
Glyoxal
C
Fumaric acid
✓
Maleic anhydride

Answer

Correct option: D.

Maleic anhydride

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MCQ 3951 Mark

Which of the following is the least reactive in the case of bromination :

A
Phenol
B
Aniline
✓
Nitrobenzene
D
Anisole

Answer

Correct option: C.

Nitrobenzene

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MCQ 3961 Mark

No. of $\pi$ electrons in the following is :

A
$2$
B
$4$
C
$5$
✓
$6$

Answer

Correct option: D.

$6$

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MCQ 3971 Mark

Which of the following is not an aromatic compound :

Answer

Correct option: B.

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MCQ 3981 Mark

Which of the following will undergo sulphonation at fastest rate ?

Answer

Correct option: B.

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MCQ 3991 Mark

Aniline under acidic medium, when chlorinated, produces :

A
$o-$ chloro aniline
✓
$m-$ chloro aniline
C
$p-$ chloro aniline
D
Mixture of ortho and para-chloro aniline

Answer

Correct option: B.

$m-$ chloro aniline

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MCQ 4001 Mark

Which of the following undergoes chlorination at fastest rate ?

Answer

Correct option: D.

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MCQ 4011 Mark

Which of the following is most reactive towards sulphonation ?

✓
$m-$ Xylene
B
$o-$ Xylene
C
Toluene
D
$p-$ Xylene

Answer

Correct option: A.

$m-$ Xylene

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MCQ 4021 Mark

Which of the following undergoes sulphonation at fastest rate ?

A
$C_6H_5NO_2$
B
$C_6H_5CH_2NO_2$
C
$C_6H_5CH_2CH_2NO_2$
✓

Answer

Correct option: D.

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MCQ 4031 Mark

Which of the following undergoes nitration fast?

Answer

Correct option: A.

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MCQ 4041 Mark

When sulphonilic acid $(p-H_2NC_6H_4SO_3H)$ is treated with excess of bromine, the product is :

✓
tribromo product
B
dibromo product
C
monobromo product
D
tetrebromo product

Answer

Correct option: A.

tribromo product

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MCQ 4051 Mark

Ring nitration of dimethyl benzene results in the formation of only one nitro dimethyl benzene. The dimethyl benzene is

A
B
✓
D
None of these

Answer

Correct option: C.

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MCQ 4061 Mark

If $p-$ methoxy toluene is nitrated, the major product is :

A
✓
C
D
No reaction

Answer

Correct option: B.

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MCQ 4071 Mark

If meta-nitroaniline is chlorinated, the major product is :

Answer

Correct option: B.

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MCQ 4081 Mark

An aromatic compound of molecular formula $C_6H_4Br_2$ was nitrated when three isomers of formula $C_6H_3Br_2NO_2$ were obtained. The original compound is :

A
$o-$ dibromobenzene
✓
$m-$ dibromobenzene
C
$p-$ dibromobenzene
D
None of these

Answer

Correct option: B.

$m-$ dibromobenzene

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MCQ 4091 Mark

Which of the following carbocations is expected to be most stable?

Answer

Correct option: D.

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MCQ 4101 Mark

The number of disubstituted products of benzene is

A
$2$
✓
$3$
C
$4$
D
$5$

Answer

Correct option: B.

$3$

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MCQ 4111 Mark

Which of the following species is expected to have maximum enthalpy in an electrophilic aromatic substitution reaction ?

✓
Species $(II)$
B
Species $(III)$
C
Species $(IV)$
D
Species $(V)$

Answer

Correct option: A.

Species $(II)$

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MCQ 4121 Mark

For the electrophilic substitution reaction involving nitration, which of the following sequence regarding the rate of reaction is true ?

A
${k_{{C_6}{H_6}}}\, > \,{k_{{C_6}{D_6}}}\, > \,{k_{{C_6}{T_6}}}$
B
${k_{{C_6}{H_6}}}\, < \,{k_{{C_6}{D_6}}}\, < \,{k_{{C_6}{T_6}}}$
✓
${k_{{C_6}{H_6}}}\, = \,{k_{{C_6}{D_6}}}\, = \,{k_{{C_6}{T_6}}}$
D
${k_{{C_6}{H_6}}}\, > \,{k_{{C_6}{D_6}}}\, < \,{k_{{C_6}{T_6}}}$

Answer

Correct option: C.

${k_{{C_6}{H_6}}}\, = \,{k_{{C_6}{D_6}}}\, = \,{k_{{C_6}{T_6}}}$

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MCQ 4131 Mark

For the electrophilic substitution reaction involving sulphonation, which of the following sequence regarding the rate of reaction is true ?

✓
${k_{{C_6}{H_6}}}\, > \,{k_{{C_6}{D_6}}}\, > \,{k_{{C_6}{T_6}}}$
B
${k_{{C_6}{H_6}}}\, < \,{k_{{C_6}{D_6}}}\, < \,{k_{{C_6}{T_6}}}$
C
${k_{{C_6}{H_6}}}\, = \,{k_{{C_6}{D_6}}}\, = \,{k_{{C_6}{T_6}}}$
D
${k_{{C_6}{H_6}}}\, > \,{k_{{C_6}{D_6}}}\, < \,{k_{{C_6}{T_6}}}$

Answer

Correct option: A.

${k_{{C_6}{H_6}}}\, > \,{k_{{C_6}{D_6}}}\, > \,{k_{{C_6}{T_6}}}$

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MCQ 4141 Mark

The order of relative reactivity of the given halides towards $S_N1$ reaction is

A
benzylchloride $> p-$ methoxybenzylchloride $> p-$ nitrobenzylchloride
✓
$p-$ methoxybenzylchloride $ > $ benzylchloride $ > p-$ nitrobenzylchloride
C
$p-$ methoxybenzylchloride $ > p-$ nitrobenzylchloride $ > $ benzylchloride
D
benzylchloride $ > p-$ nitrobenzylchloride $ > p-$ methoxybenzylchloride

Answer

Correct option: B.

$p-$ methoxybenzylchloride $ > $ benzylchloride $ > p-$ nitrobenzylchloride

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MCQ 4151 Mark

Which reaction is not named as Friedal Craft's reaction

Answer

Correct option: D.

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MCQ 4161 Mark

To prepare $A$ from $B$ the correct sequence of reagents can be

A
$Cl_2\ /\ AlCl_3\ ;\ Mg(THF)\ ;\ O_2\ /\ H^+$
B
$HNO_3\ +\ H_2SO_4\ ;\ Sn\ +\ HCl\ ;\ NaNO_2\ +\ HCl\ ;$ Steam
C
$CH_3-CH=CH_2\ /\ H^+\ ;\ O_2\ /\ hv\ ;\ H^+$
✓
All of these

Answer

Correct option: D.

All of these

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MCQ 4171 Mark

Which of the following nonaromatic in nature

Answer

Correct option: A.

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MCQ 4181 Mark

Which of the following represents Huckle's rule

A
$(4n)\pi \,{e^\Theta }$
✓
$(4n+2)\pi \,{e^\Theta }$
C
$(4n+1)\pi \,{e^\Theta }$
D
$(2n+2)\pi \,{e^\Theta }$

Answer

Correct option: B.

$(4n+2)\pi \,{e^\Theta }$

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MCQ 4191 Mark

Complete the following reactions and identify $A, B\,C$ respectively

A
$A = Ni, B = H_2O\, (liquid), C = H_2O$
✓
$A = Zn, B = H_2O \,(steam), C = H_2 (Ni-Al\, alloy)$
C
$A = Mg, B = H_2O \,(liquid), C = HCl$
D
$A = Zn, B = H_2O \,(boiling), C = SnCl_2$

Answer

Correct option: B.

$A = Zn, B = H_2O \,(steam), C = H_2 (Ni-Al\, alloy)$

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MCQ 4201 Mark

In the ration,

$X$ and $Y$ respectively are :-

✓
$C_6H_5Cl$ and $C_6H_5SO_3H$
B
$C_6H_5Cl$ and $C_6H_5OH$
C
$C_6H_4Cl_2$ and $C_6H_5SO_2$
D
$C_6H_5Cl$ and $C_6H_5CHO$

Answer

Correct option: A.

$C_6H_5Cl$ and $C_6H_5SO_3H$

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MCQ 4211 Mark

$Ca + C\xrightarrow[\Delta ]{}A\xrightarrow{{{H_2}O}}B\xrightarrow[{cyclic\,polymerisation}]{}C$

Product $B$ and $C$ are respectively

A
$CH_4$ and polythene
✓
$C_2H_2$ and Benzene
C
$C_2H_4$ and polythene
D
$C_2H_4$ and Benzene

Answer

Correct option: B.

$C_2H_2$ and Benzene

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MCQ 4221 Mark

Which of the following reaction is called as wurtz fittig reaction ?

Answer

Correct option: C.

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MCQ 4231 Mark

Product $A$ in the reaction will be

Answer

Correct option: A.

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MCQ 4241 Mark

Above reaction is known as

A
Wurtz reaction
B
Wurtz fittig reaction
✓
Fittig reaction
D
Kolbe electrolysis

Answer

Correct option: C.

Fittig reaction

c
$(c)$ Aryl-halide is used.
$\therefore$ It is known as Wurtz fittig reaction

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MCQ 4251 Mark

Product $(B)$ in the above reaction is

Answer

Correct option: B.

b
in forward direction

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MCQ 4261 Mark

Cycloalkane has the formula

A
${C_n}{H_{2n + 2}}$
B
${C_n}{H_{2n - 2}}$
✓
${C_n}{H_{2n}}$
D
${C_{2n}}{H_2}$

Answer

Correct option: C.

${C_n}{H_{2n}}$

c
It’s obvious.

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MCQ 4271 Mark

Which is the example of branch isomerization

✓
$\mathop {\mathop {\mathop {\mathop {C - C - C}\limits^| }\limits^C }\limits_{} }\limits_{} - C$ -C and $\mathop {\mathop {\mathop {\mathop {C - C - C}\limits^| }\limits^C }\limits_| }\limits_C $
B
$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C - C - C} \\
| \\
C
\end{array}$ and $\begin{array}{*{20}{c}}
{C\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C - C - C} \\
| \\
C
\end{array}$
C
D
$C - C - C - C$ and $\begin{array}{*{20}{c}}
{C - C - C} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C}
\end{array}$

Answer

Correct option: A.

$\mathop {\mathop {\mathop {\mathop {C - C - C}\limits^| }\limits^C }\limits_{} }\limits_{} - C$ -C and $\mathop {\mathop {\mathop {\mathop {C - C - C}\limits^| }\limits^C }\limits_| }\limits_C $

a
It’s obvious.

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MCQ 4281 Mark

The decreasing order of boiling points is

✓
$n-$ Pentane > iso-Pentane > neo-Pentane
B
iso-Pentane > $ n-$ Pentane > neo-Pentane
C
neo-Pentane > iso-Pentane >$ n-$ Pentane
D
$n-$ Pentane > neo-Pentane > iso-Pentane

Answer

Correct option: A.

$n-$ Pentane > iso-Pentane > neo-Pentane

a
As the boiling point of an alkane depends on the surface area of a molecule, higher the surface is, higher the boiling point of alkane. The branched-chain isomer of an alkane has a lower surface area than that of its straight-chain isomer, so the branched-chain isomer of an alkane has a lower boiling point than its straight-chain isomer.

So, higher the branches, lower is the boiling point.

So, the order of boiling point of isomeric pentanes is $n -$ pentane $\,>\,$ iso $-$ pentane $\,>\,$ neo $-$ pentane.

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MCQ 4291 Mark

To prepare a pure sample of $n-$ hexane using sodium metal as one reactant, the other reactant will be

✓
$n-$ propyl bromide
B
Ethyl bromide and $ n-$ butyl bromide
C
Ethyl chloride and $ n-$ butyl chloride
D
Methyl bromide and $ n -$ pentyl chloride

Answer

Correct option: A.

$n-$ propyl bromide

a
(a) According to wurtz reaction

$2C{H_3}C{H_2}C{H_2}Br + 2Na\xrightarrow{{ether}}$ $C{H_3}{(C{H_2})_4}C{H_3} + 2NaBr$

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MCQ 4301 Mark

Sodium acetate can be converted to ethane by

A
Heating with $LiAl{H_4}$
✓
Electrolysing its aqueous solution
C
Heating with sodalime
D
Heating with calcium acetate

Answer

Correct option: B.

Electrolysing its aqueous solution

b
(b) $\mathop {2C{H_3}COONa}\limits_{{\text{Sodium}}\,{\text{acetate}}} + 2{H_2}O\xrightarrow{{{\text{Electolysis}}}}\,C{H_3} - C{H_3} + 2C{O_2} + 2NaOH + {H_2}$

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MCQ 4311 Mark

Which of the following compounds is used in antiknock compositions to prevent the deposition of oxides of lead on spark plug, combustion chamber and exhaust pipe

A
Glycerol
B
Glycol
✓
$1, 2-$ dibromoethane
D
Benzene

Answer

Correct option: C.

$1, 2-$ dibromoethane

c
(c) $Pb{({C_2}{H_5})_4} \overset {heat} \longrightarrow Pb + \mathop {4C{H_3}CH_2^{}}\limits_{{\rm{Ethyl}}\,{\rm{radical}}} $

$\begin{array}{*{20}{c}}
{C{H_2} - C{H_2}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,} \\
{\,Br\,\,\,\,\,\,\,\,Br\,\,\,\,\,\,}
\end{array}$ $ + Pb \to \mathop {C{H_2} = C{H_2}}\limits_{Ethene} + \mathop {PbB{r_2}}\limits_{Leadbromide} $

As leaded gasoline burns, lead metal gets deposited in the engine which is removed by adding ethylene dibromide. The lead bromide is volatile and is carried off with the exhaust gases from the engine

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MCQ 4321 Mark

Which of petroleum corresponds to kerosene oil

A
${C_{15}} - {C_{18}}$
✓
${C_{10}} - {C_{12}}$
C
${C_5} - {C_9}$
D
${C_1} - {C_9}$

Answer

Correct option: B.

${C_{10}} - {C_{12}}$

b
Kerosene is a mixture of hydrocarbons. The chemical composition depends on its source of isolation, usually, it consists of about $10$ different hydrocarbons, each containing $11$ to $16$ carbon atoms per molecule.

The main constituents are saturated straight-chain and branched-chain hydrocarbons which are also called as paraffin, as well as ring-shaped cycloparaffins which are also known as naphthenes. Kerosene is less volatile liquid than gasoline.

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MCQ 4331 Mark

In the reaction $C{H_3} - Br + 2Na + Br - C{H_3} \to $, the product called

✓
Wurtz reaction
B
Aldol condensation
C
Perkin’s reaction
D
Levit reaction

Answer

Correct option: A.

Wurtz reaction

a
Typically, you would react two alkyl halides to form an alkane that consists of their respective $R$ groups. So, as an example, you would have:

$CH _3 Br + CH _3 Cl \stackrel{ Na ( s )}{\longrightarrow} CH _3 CH _3$

(with loss of $NaCl$ and then $NaBr$ )

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MCQ 4341 Mark

Iodoethane reacts with sodium in the presence of dry ether. The product is

A
Pentane
B
Propane
C
Butene
✓
Butane

Answer

Correct option: D.

Butane

d
(d) ${C_2}{H_5}I + 2Na + I{C_2}{H_5} \xrightarrow[Dry]{Ether} \mathop {}\limits_{{\rm}} \mathop {{C_2}{H_5} - {C_2}{H_5}}\limits_{{\rm{Butane}}} + 2NaI$

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MCQ 4351 Mark

Which of the following is oxidised by $KMn{O_4}$

A
Methane
B
Pentane
✓
Isobutane
D
Neopentane

Answer

Correct option: C.

Isobutane

c
(c) ${(C{H_3})_3}CH \xrightarrow{KMnO_4} \,\,\,\mathop {{{(C{H_3})}_3}C - OH}\limits_{{\rm{tertiary \,butyl \,alcohol}}} $

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MCQ 4361 Mark

The most volatile compound is

✓
$2, 2-$ dimethyl propane
B
$2-$ methyl butane
C
Isobutane
D
$n-$ pentane

Answer

Correct option: A.

$2, 2-$ dimethyl propane

a
The boiling point is inversely proportional to the branch in the compound. Therefore, $2,2$-dimethyl propane has more branching, higher boiling point.

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MCQ 4371 Mark

In Wurtz reaction, the reagent used is

A
$Na$
B
$Na$ / liquid $NH_3$
✓
$Na$ / Dry ether
D
$Na$ / Dry alcohol

Answer

Correct option: C.

$Na$ / Dry ether

c
(c) $RCl + 2Na + RCl \xrightarrow[Ether]{Dry} \mathop {} 2NaCl + \mathop {R - R}\limits_{{\rm{Alkane}}} $

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MCQ 4381 Mark

Which of the following has highest octane number

A
$n-$ hexane
B
$n - $ heptane
C
$n-$ pentane
✓
$2, 2, 4-$ trimethyl pentane

Answer

Correct option: D.

$2, 2, 4-$ trimethyl pentane

d
(d) iso-octane i.e. $2,2,4-$ trimethyl pentane has highest octane number.

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MCQ 4391 Mark

The petrol having octane number $80$ has

✓
$20\%$ normal heptane + $80\%$ iso-octane
B
$80\%$ normal heptane + $20\%$ iso-octane
C
$20\%$ normal heptane + $80\%$ normal octane
D
$80\%$ normal heptane + $20\%$ normal octane

Answer

Correct option: A.

$20\%$ normal heptane + $80\%$ iso-octane

a
Petrol, which has octane number $80$ contain $20 \,\%\, n$-heptane and $80\, \%$ isooctane.

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MCQ 4401 Mark

Which of the following reactions will not give propane

A
$C{H_3}C{H_2}C{H_2}Cl\mathop {}\limits_{} $ $ \xrightarrow[H_2O]{Mg/ether} $
✓
$C{H_3}COCl\mathop {}\limits_{} $ $ \xrightarrow[H_2O]{CH_3MgX} $
C
$C{H_3}CH = C{H_2}\mathop {}\limits_{} $ $ \xrightarrow[B_2h_6]{CH_3COOH} $
D
$\begin{array}{*{20}{c}}
{C{H_3}CH - C{H_3}} \\
{|\,\,\,\,\,\,\,\,} \\
{OH\,\,\,\,}
\end{array}$ $ \xrightarrow{P/HI} $

Answer

Correct option: B.

$C{H_3}COCl\mathop {}\limits_{} $ $ \xrightarrow[H_2O]{CH_3MgX} $

b
(b) With calculated amount of Grignard reagent, acetyl chloride forms ketones.

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MCQ 4411 Mark

Which of the following are produced from coal tar

A
Synthetic dyes
B
Drugs
C
Perfumes
✓
All the three

Answer

Correct option: D.

All the three

d
(d) Synthetic dyes, drugs, perfumes all are made from coal tar.

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MCQ 4421 Mark

In alkanes, the bond angle is.....$^o$

✓
${109.5}$
B
${109}$
C
${120}$
D
${180}$

Answer

Correct option: A.

${109.5}$

a
(a) In alkanes, hybridization is $s{p^3}$. Hence bond angle is ${109^o}.5'$.

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MCQ 4431 Mark

In the preparation of alkanes; a concentrated aqueous solution of sodium or potassium salts of saturated carboxylic acid are subjected to

A
Hydrolysis
B
Oxidation
C
Hydrogenation
✓
Electrolysis

Answer

Correct option: D.

Electrolysis

d
(d) $2C{H_3}COONa + 2{H_2}O\, \xrightarrow{Electrolysis} \,\,\,C{H_3} - C{H_3} + 2C{O_2} + 2NaOH + {H_2}$

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MCQ 4441 Mark

Halogenation of alkanes is an example of

A
Electrophilic substitution
B
Nucleophilic substitution
✓
Free-radical substitution
D
Oxidation

Answer

Correct option: C.

Free-radical substitution

c
Halogenation of alkanes is carried out in the presence of photochemical conditions.

Under photochemical conditions, the halogens will break homolytically and forms radical. The halogen radical will abstract hydrogen from alkanes. Now the alkyl radical can combine with alkyl radical or it can also combine with halogen radical forming alkyl radicals.

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MCQ 4451 Mark

Propionic acid is subjected to reduction with hydroiodic acid in the presence of a little P, the product formed is

A
Ethane
✓
Propane
C
Butane
D
None of these

Answer

Correct option: B.

Propane

b
(b) $\mathop {C{H_3} - C{H_2} - COOH}\limits_{{\rm{Propanoic}}\,{\rm{acid}}} + 6HI \,\,\xrightarrow{Red P} \,\,\mathop {C{H_3} - C{H_2} - C{H_3}}\limits_{{\rm{Propane}}} + 2{H_2}O + 3{I_2}$

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MCQ 4461 Mark

When ethyl iodide and propyl iodide react with $Na$ in the presence of ether, they form

A
One alkane
B
Two alkanes
C
Four alkanes
✓
Three alkanes

Answer

Correct option: D.

Three alkanes

d
(d) $\mathop {C{H_3} - C{H_2} - C{H_3}}\limits_{{\rm{Propane}}} + 2{H_2}O + 3{I_2}$ $ \xrightarrow[Ether]{Dry} $ $\mathop {{C_2}{H_5} - {C_3}{H_7}}\limits_{{\rm{Pentane}}} + 2NaI$

${C_2}{H_5}I + 2Na + {C_2}{H_5}I\mathop {}\limits_{{\rm{}}} \xrightarrow[Ether]{Dry} \mathop {{C_2}{H_5} - {C_2}{H_5}}\limits_{{\rm{Butane}}} + 2NaI$

${C_3}{H_7}I + 2Na + {C_3}{H_7}I\mathop {\xrightarrow{{Dry}}}\limits_{Ether} \mathop {{C_3}{H_7} - {C_3}{H_7}}\limits_{{\text{Hexane}}} + 2NaI$

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MCQ 4471 Mark

The alkane that yields two isomeric monobromo derivatives is

A
Neopentane
B
Ethane
C
Methane
✓
Propane

Answer

Correct option: D.

Propane

d
Two isomeric monochloro derivatives of Propane are:

$1$-chloro propane $( CH _3- CH _2-CH_2(Cl))$ and $2$-chloro propane $( CH _3 - CH ( Cl )- CH _3 \text { ) }$

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MCQ 4481 Mark

Kerosene is a mixture of

✓
Alkanes
B
Aromatic compounds
C
Alcohols
D
Aliphatic acids

Answer

Correct option: A.

Alkanes

a
Kerosene is a thin, clear liquid formed from hydrocarbons obtained from the fractional distillation of petroleum between $150^{\circ} C$ and $275^{\circ} C$, resulting in a mixture with a density of $0.78-0.81\, g / cm ^3$.It is composed of carbon chains that typically contain between $6$ and $16$ carbon atoms per molecule. It is miscible in petroleum solvents but immiscible in water. Kerosene's major components are branched and straight chain alkanes and naphthenes (cycloalkanes), which normally account for at least $70 \,\%$ by volume.

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MCQ 4491 Mark

When petroleum is heated the vapours contain mainly

A
Kerosene
✓
Petroleum ether
C
Diesel
D
Machine oil

Answer

Correct option: B.

Petroleum ether

b
Petroleum ether because due to it's lowest boiling point

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MCQ 4501 Mark

Iso-octane is mixed to the petrol

A
To precipitate inorganic substances
B
To prevent freezing of petrol
C
To increase boiling point of petrol
✓
As an antiknock

Answer

Correct option: D.

As an antiknock

d
One member of the octane family, isooctane, is used as a reference standard to benchmark the tendency of gasoline or $LPG$ fuels to resist self-ignition. For example, gasoline with the same knocking characteristics as a mixture of $90 \,\%$ iso-octane and $10 \,\%$ heptane would have an octane rating of $90$

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MCQ 4511 Mark

Tetraethyl lead is used as

A
Fire extinguisher
B
Pain reliever
✓
Petroleum additive
D
Mosquito repellent

Answer

Correct option: C.

Petroleum additive

c
Tetraethyl lead is used as petroleum additive to prevent knocking of engine.

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MCQ 4521 Mark

Cyclohexane, a hydrocarbon floats on water because

A
It is immiscible with water
B
Its density is low as compared to water
C
It is non-polar substance
✓
It is immiscible and lighter than water

Answer

Correct option: D.

It is immiscible and lighter than water

d
(d) Cyclohexane, is immiscible and lighter than water. Hence, floats on the surface of water.

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MCQ 4531 Mark

Natural gas contains mainly

✓
Methane
B
$n-$ butane
C
$n-$ octane
D
Mixture of octane

Answer

Correct option: A.

Methane

a
(a) Methane is the main component of natural gas.

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MCQ 4541 Mark

The organic compound used as antiknock agent in petroleum is

✓
${({C_2}{H_5})_4}Pb$
B
$TNT$
C
$C{H_3}MgBr$
D
${({C_2}{H_5})_2}Hg$

Answer

Correct option: A.

${({C_2}{H_5})_4}Pb$

a
This abnormal combustion produces a specific type of sound, which we call knocking.

Knocking has adverse effects. It results in early wear-and-tear of the piston. Carbon is deposited in the inner part of the cylinders [Internal Combustion Engines have cylinders, inside which pistons move]. Also, Efficiency is reduced.

So we want to reduce knocking. We add something which can reduce it. Such substances are called Anti - knockingAgents.

A popular anti-knocking agent was Tetra Ethyl Lead (TEL) $\left( C _2 H _5\right)_4 Pb$.

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MCQ 4551 Mark

Which of the following statements is incorrect. The members of the homologous series of alkanes

✓
Are all straight chain compounds
B
Have the general formula ${C_n}{H_{2n + 2}}$
C
Have similar chemical properties
D
Show a regular gradation of physical properties

Answer

Correct option: A.

Are all straight chain compounds

a
All the members of the homologous series of alkanes are not straight chain compounds they can be branched, but differ by $- CH _2$ group.

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MCQ 4561 Mark

A liquid hydrocarbon can be converted to gaseous hydrocarbon by

✓
Cracking
B
Hydrolysis
C
Oxidation
D
Distillation under reduced pressure

Answer

Correct option: A.

Cracking

a
(a) $\underset{\text{Liquid}}{\mathop{\underset{\text{Hexane}}{\overset{{}}{\mathop{{{C}_{6}}{{H}_{14}}}}}\,}}\,\xrightarrow{\Delta }\underset{\text{Butane}}{\mathop{{{C}_{4}}{{H}_{10}}}}\,+\underset{\text{Gas}}{\mathop{\underset{\text{Ethene}}{\mathop{{{C}_{2}}{{H}_{2}}}}\,}}\,$

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MCQ 4571 Mark

Formation of alkane by the action of $Zn$ on alkyl halide is called

✓
Frankland's reaction
B
Wurtz reaction
C
Cannizzaro reaction
D
Kolbe's reaction

Answer

Correct option: A.

Frankland's reaction

a
$(i)$ wurtz reaction

$2 RX +2 Na \stackrel{\text { Ether }}{\longrightarrow} \underset{\text { alkane }}{ R - R }$

$(ii)$ Kolbe's reaction

$RCOONa + H _2 O \stackrel{\text { Electrolysis }}{\longrightarrow} \underset{\text { alkane }}{ R - R }$

$(iii)$ Ulmann's reaction

$2 C _6 H _5 I +2 Cu \rightarrow \underset{\text { biphenyl } }{ C _6 H _5}- C _6 H _5$

$(iv)$ Frankland reaction

$\underset{\text { alkyl halide }}{2 RX }+ Zn \rightarrow \underset{\text { alkane }}{ R - R }$

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MCQ 4581 Mark

Which of the following compounds will form a hydrocarbon on reaction with Grignard reagent

✓
$C{H_3}C{H_2}OH$
B
$C{H_3}CHO$
C
$C{H_3}COC{H_3}$
D
$C{H_3}C{O_2}C{H_2}$

Answer

Correct option: A.

$C{H_3}C{H_2}OH$

a
(a) Compounds having active hydrogen $\left( {ROH,{H_2}O,R - N{H_2}} \right)$ can form alkane when treated with Grignard’s reagent

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MCQ 4591 Mark

Name the hydrocarbon that is a liquid at $STP$

A
Ethane
B
Propane
C
$n-$ butane
✓
$n-$ pentane

Answer

Correct option: D.

$n-$ pentane

d
Lower hydrocarbons which contain up to $4$ carbon atoms are gases at room temperature whereas higher hydrocarbons are liquid at room temperature. Thus $N - P$ entane is liquid at room temperautre.

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MCQ 4601 Mark

Which statement is not true concerning alkanes

✓
Large number alkanes are soluble in water
B
All alkanes have a lower density than water
C
At room temperature some alkanes are liquids, some solids and some gases
D
All alkanes burn

Answer

Correct option: A.

Large number alkanes are soluble in water

a
No alkanes are not soluble in water. Water is a polar solvent and has hydrogen bonding. For any compound to be soluble in water, it should be polar or have hydrogen bonding in it.

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MCQ 4611 Mark

Fischer Tropsch process is used for the manufacture of

✓
Synthetic petrol
B
Thermosetting plastics
C
Ethanol
D
Benzene

Answer

Correct option: A.

Synthetic petrol

a
The Fisher-Tropscgh process is used in the manufacturing of Syntheticpetrol. The Fischer-Tropsch process is a collection of chemical reactions that converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons.... In the usual implementation, carbon monoxide and hydrogen, the feedstocks for $FT$, are produced from coal, natural gas, or biomass in a process known as gasification.

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MCQ 4621 Mark

Which one of the following compounds cannot be prepared by Wurtz reaction

✓
$C{H_4}$
B
${C_2}{H_6}$
C
${C_3}{H_8}$
D
${C_4}{H_{10}}$

Answer

Correct option: A.

$C{H_4}$

a
(a)It is not possible to prepare $C{H_4}$ by wurtz reaction.

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MCQ 4631 Mark

A fuel contains $25 \%$ $n-$ heptane and $75 \%$ iso-octane. Its octane number is

A
$50$
✓
$75$
C
$100$
D
$25$

Answer

Correct option: B.

$75$

b
(b) Octane number is the percentage by volume of is $o-$ octane in the mixture of iso- octane and $n-$ heptane which has the same antiknocking properties as the fuel under examination.
Given fuel ($25\%$ $n- $ heptane + $75\%$ iso- octane) Hence, octane number = $75$ (because iso octane is $75\%$)

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MCQ 4641 Mark

Which of the following has highest percentage of hydrogen

✓
$C{H_4}$
B
${C_2}{H_4}$
C
${C_6}{H_6}$
D
${C_2}{H_2}$

Answer

Correct option: A.

$C{H_4}$

a
(a) $\%$ of hydrogen = $\frac{Mass\,\, of\,\, hydrogen}{Mass \,\,of\, \,compond} \times 100$

$C{H_4} = \frac{4}{{16}}\; \times \;100\; = \;25\% $.

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MCQ 4651 Mark

What is the molecular formula of the alkane, the $5.6 \,litre$ of which weight $11 \,g$ at $STP$

A
${C_6}{H_{14}}$
B
${C_4}{H_{10}}$
✓
${C_3}{H_8}$
D
${C_2}{H_6}$

Answer

Correct option: C.

${C_3}{H_8}$

c
(c) Molecular mass can be obtained by the victor mayer process

${\rm{Molecular}}\,\,{\rm{mass}} = \frac{{{\rm{Weight}}\,}}{{V\,ml.}} \times {\rm{22400}}$

$ = \frac{{{\rm{11}}}}{{{\rm{5600}}}} \times 22400 = 44$

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MCQ 4661 Mark

The reference compound `iso-octane' which is used in determining the octane number of gasoline has the structure

A
$C{H_3} - CH(C{H_3}) - CH(C{H_3}) - CH(C{H_3}) - C{H_3}$
✓
$C{H_3} - C{(C{H_3})_2} - C{H_2} - CH(C{H_3}) - C{H_3}$
C
$C{H_3} - C{(C{H_3})_2} - CH(C{H_3}) - C{H_2} - C{H_3}$
D
$C{H_3} - C{(C{H_3})_2} - C{(C{H_3})_2} - C{H_3}$

Answer

Correct option: B.

$C{H_3} - C{(C{H_3})_2} - C{H_2} - CH(C{H_3}) - C{H_3}$

b
The octane number of gasoline is a way of knocking down its resistance. The characteristics of octane number one gasoline are compared by isoacetane ($2,2,4$-trimethylparnane) and heptane. Isooctane is assigned an octane number of $100$ . It is a highly branching compound that burns easily, with little knock.

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MCQ 4671 Mark

Petroleum ether can be used as

✓
Solvent for fat, oil, varnish and rubber
B
As a fuel
C
Both $(a)$ and $(b)$
D
None of these

Answer

Correct option: A.

Solvent for fat, oil, varnish and rubber

a
(a)Solvent for fat, oil, varnish and rubber

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MCQ 4681 Mark

The order of appearance of the following with rising temperature during the refining of crude oil is

A
Kerosene oil, gasoline, diesel
B
Diesel, gasoline, kerosene oil
C
Gasoline, diesel, kerosene oil
✓
Gasoline, kerosene oil, diesel

Answer

Correct option: D.

Gasoline, kerosene oil, diesel

d
(d) Gasoline, kerosene oil, diesel

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MCQ 4691 Mark

When sodium propionate is heated with soda lime, the main product is

✓
Ethane
B
Methane
C
Propane
D
Butane

Answer

Correct option: A.

Ethane

a
(a) $C{H_3} - C{H_2} - COONa \xrightarrow[\Delta]{Soda lime} \mathop {}\limits C{H_3} - C{H_3}$

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MCQ 4701 Mark

Gasoline is a mixture of alkanes with the number of carbon atoms

A
${C_3} - {C_5}$
B
${C_5} - {C_6}$
C
${C_6} - {C_8}$
✓
${C_7} - {C_9}$

Answer

Correct option: D.

${C_7} - {C_9}$

d
(d) Gasoline or petrol composition ${C_7} - {C_{12}}$.

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MCQ 4711 Mark

The final product of complete oxidation of hydrocarbons is

A
Acid
B
Aldehyde
✓
${H_2}O + C{O_2}$
D
Dihydric alcohol

Answer

Correct option: C.

${H_2}O + C{O_2}$

c
(c) $\mathop {C{H_4}}\limits_{{\rm{Methane}}} + 2{O_2} \to C{O_2} + 2{H_2}O$

$\mathop {{C_2}{H_4}}\limits_{{\rm{Ethene}}} + 3{O_2} \to 2C{O_2} + 2{H_2}O$

All hydrocarbons saturated or unsaturated on complete combustion always produce $C{O_2}$ and ${H_2}O$.

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MCQ 4721 Mark

Which of the following represents the most oxidized form of hydrocarbon

✓
$C{O_2}$
B
$RCHO$
C
$RCOOH$
D
$RCOOOH$

Answer

Correct option: A.

$C{O_2}$

a
(a) Hydrocarbons on complete oxidation produce $C{O_2}$ and water

$C{H_3} - C{H_3} + 3\frac{1}{2}{O_2} \to 2\,C{O_2} + 3{H_2}O$

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MCQ 4731 Mark

Name the reaction

${C_{10}}{H_{22}} \xrightarrow{900\,K} {C_4}{H_8} + {C_6}{H_{14}}$

A
Alkylation
✓
Cracking
C
Pyrolysis
D
Fractionation

Answer

Correct option: B.

Cracking

b
(b) $\mathop {{C_{10}}{H_{22}}}\limits_{{\rm{Decane}}} \mathop {}\limits_{{\rm{}}} \xrightarrow[Cracking]{900\,K} \mathop {{C_4}{H_8}}\limits_{{\rm{Butane}}} + \mathop {{C_6}{H_{14}}}\limits_{{\rm{Hexane}}} $

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MCQ 4741 Mark

How many types of carbon atoms are present in $ 2, 2, 3-$ trimethylpentane

A
$1$
B
$2$
C
$3$
✓
$4$

Answer

Correct option: D.

$4$

d
It’s obvious.

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MCQ 4751 Mark

At room temperature solid paraffin is

A
${C_3}{H_8}$
B
${C_8}{H_{18}}$
C
${C_4}{H_{10}}$
✓
${C_{20}}{H_{42}}$

Answer

Correct option: D.

${C_{20}}{H_{42}}$

d
$n$-Icosane (the straight-chain structural isomer of icosane) $\left( C _{20} H _{42}\right)$ is the shortest compound found in paraffin waxes used to form candles.

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MCQ 4761 Mark

Which one of the following compounds does not give addition reactions

A
Aldehydes
✓
Alkanes
C
Alkenes
D
Alkynes(e)Ketones(f)All of these

Answer

Correct option: B.

Alkanes

b
(b) Alkanes do not give addition reactions because multiple bond is absent.

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MCQ 4771 Mark

The inorganic origin of petroleum is indicated by the fact that

A
Its constituents can be separated by fractional distillation
✓
Carbon and hydrocarbon can combine by absorption of solar energy to give hydrocarbons
C
Petroleum contains traces of chlorophyll
D
Oil fields are located with the help of seismograph

Answer

Correct option: B.

Carbon and hydrocarbon can combine by absorption of solar energy to give hydrocarbons

b
Abiogenesis-inorganic origin of petroleum is the oldest theory which suggests that petroleum comes from the underneath part of the mantle very long time ago before the existence of life on earth. Carbon and hydrocarbon can combine by absorption of solar energy to give hydrocarbons.

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MCQ 4781 Mark

Which of the following is a gemdihalide

A
$C{H_3}.CHBr.CHBr.C{H_3}$
B
$C{H_2}Br.C{H_2}Br$
C
$CHBr = CHBr$
✓
$C{H_3}CHB{r_2}$

Answer

Correct option: D.

$C{H_3}CHB{r_2}$

d
(d) In gemdihalide both the halogen atoms are present on the same carbon atom while in vicdihalide both the halogen atoms are present on adjacent carbon atoms.

$\mathop {C{H_3} - CHB{r_2}}\limits_{{\rm{Gemdihalide}}} $ $\mathop {\mathop {C{H_2}}\limits_{\mathop {|\,\,\,\,\,\,\,}\limits_{Br\,\,\,} } - \mathop {C{H_2}}\limits_{\mathop {|\,\,\,\,\,\,\,\,}\limits_{Br\,\,\,\,} } }\limits_{vic{\rm{ - }}{\rm{dihalide}}} $

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MCQ 4791 Mark

Which one of the following contain isopropyl group

A
$2,2,3,3-$tetramethylpentane
✓
$2-$methylpentane
C
$2,2,3-$trimethylpentane
D
$3,3-$dimethylpentane

Answer

Correct option: B.

$2-$methylpentane

b
(b) $\mathop {\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{{H_3}C - {H_2}C - C - C - C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}\,\,\,C{H_3}}
\end{array}}\limits_{2,3,3,3 - tetramethylpen\tan e} $

$\mathop {{H_3}C - {H_2}C - \mathop {\mathop {{H_2}C - HC - C{H_3}}\limits^{\,\,\,\,|} }\limits^{\,\,\,\,\,\,\,\,\,C{H_3}} }\limits_{{\rm{isopropyl group 2 - methylpentane}}} $

$\mathop {\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}\,\,\,C{H_{3\,}}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{{H_3}C - {H_2}C - HC - C - C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}}\limits_{2,2,3 - trimethylpen\tan e} $

$\mathop {\mathop {\mathop {\mathop {\mathop {{H_3}C - {H_2}C - C - C{H_2} - C{H_3}}\limits^{\,\,|} }\limits^{\,\,\,\,\,\,\,\,C{H_3}} }\limits_{\,|} }\limits_{\,\,\,\,\,\,C{H_3}} }\limits_{{\rm{3, 3 - dimethylpentane}}} $

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MCQ 4801 Mark

By Wurtz reaction, a mixture of methyliodide and ethyliodide gives

A
Butane
B
Ethane
C
Propane
✓
A mixture of the above three

Answer

Correct option: D.

A mixture of the above three

d
(d) All-butane, Ethane and Propane are possible in this reaction.

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MCQ 4811 Mark

Isomerism in saturated hydrocarbons is due to

A
Change in the valence of carbon
B
Change in the ratio of elements in compounds
✓
Formation of branches in the chain of $C$ atoms
D
Formation of double bond

Answer

Correct option: C.

Formation of branches in the chain of $C$ atoms

c
(c) Formation of branches in the chain of $C$ atoms

$\mathop {C - C - C - C}\limits_{{\rm{straight chain}}} $ $\mathop {C - \mathop C\limits_{\mathop |\limits_C } - C}\limits_{{\rm{Branched chain}}} $

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MCQ 4821 Mark

Photochemical chlorination of alkane is initiated by a process of

A
Pyrolysis
B
Substitution
✓
Homolysis
D
Peroxidation

Answer

Correct option: C.

Homolysis

c
(c) Chlorination of alkane in photochemical reaction which takes place by free radical mechanism. Free radicals are formed by homolytic bond fission or homolysis.

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MCQ 4831 Mark

Which of the following is not linked with methane

A
Marsh gas
B
Natural gas
✓
Producer gas
D
Coal gas

Answer

Correct option: C.

Producer gas

c
(c) Marsh gas, Natural gas and coal gas contains $C{H_4}$ but producer gas is a mixture of $CO$ and ${N_2}$

$ \underset {Coke \,Red \,hot} {2C} \, + \underbrace {O_2 \, + 4N_2}_\text {Air} \, \longrightarrow \, \underbrace {2CO \, + \,4N_2}_\text {Producer $\,$gas} $

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MCQ 4841 Mark

Which of the following has highest octane number

A
n-hexane
B
n-heptane
✓
Iso-octane
D
n-heptane and iso-octane mixed in ratio $ 50 : 50$

Answer

Correct option: C.

Iso-octane

c
An aromatic compound has the highest octane number. The octane number of aromatic hydrocarbons are exceptionally high.

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MCQ 4851 Mark

Most of the hydrocarbons from petroleum are obtained by

✓
Fractional distillation
B
Fractional crystallization
C
Vaporization
D
Polymerization

Answer

Correct option: A.

Fractional distillation

a
(a) Fractional distillation is based on the difference in the boiling point of different components.

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MCQ 4861 Mark

In the dichlorination reaction of propane, mixture of products are obtained. How many isomers, the mixture contains

A
$2$
B
$3$
✓
$4$
D
$5$

Answer

Correct option: C.

$4$

c
The mixture will contains $4$ isomers.

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MCQ 4871 Mark

Grignard reagent is not prepared in aqueous medium but prepared; in ether medium because the reagent

✓
Reacts with water
B
Is insoluble in water
C
Is highly reactive in ether
D
Becomes inactive in water

Answer

Correct option: A.

Reacts with water

a
Grignard reagent is not prepared in aqueous medium. It is prepared in ether medium because the reagent reacts with water. Slight traces of moisture will prevent the reaction.

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MCQ 4881 Mark

A sample of petrol is a mixture of $30\%$ $n-$heptane and $70\%$ iso-octane. The sample has octane number

A
$30$
✓
$70$
C
$15$
D
$35$

Answer

Correct option: B.

$70$

b
(b) Petrol sample $30\%$ $n-$heptane + $70\%$ iso-octane since iso-octane is $70\%$. Hence, octane no. is $70$.

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MCQ 4891 Mark

For the reduction of ketones to hydrocarbon, the appropriate agent is

A
$HI$
✓
$Zn - Hg/HCl$
C
Red phosphorous
D
${H_2}S{O_4}$

Answer

Correct option: B.

$Zn - Hg/HCl$

b
Clemmensen reduction aldehydes and ketones are reduced to the corresponding alkanes by means of amalgamated $Zn - Hg$ and $HCl$.

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MCQ 4901 Mark

Heating of alkanes with fuming sulphuric acid or oleum at high temperature, which forms sulphonic acid, is called

A
Nitration
B
Halogenation
✓
Sulphonation
D
Oxidation

Answer

Correct option: C.

Sulphonation

c
Heating of alkanes with fuming sulphuric acid or oleum at high temperature, which form sulphonic acid, is called Sulphonation.

$H _2 S _2 O _7 \text { (Oleum) } \rightarrow H _2 SO _4+ SO _3$

$R - H + SO _3 \rightarrow R - SO _2 OH$

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MCQ 4911 Mark

Daily use candles (paraffin wax) contain

✓
Higher saturated hydrocarbon
B
Lower saturated hydrocarbon
C
Higher unsaturated hydrocarbon
D
Lower unsaturated hydrocarbon

Answer

Correct option: A.

Higher saturated hydrocarbon

a
Candles consist of paraffin wax which generally contains saturated hydrocarbons of length more than $C _{24}$.

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MCQ 4921 Mark

Normal butane convert into isobutane by

A
$LiAl{H_4}$
✓
$AlC{l_3}$
C
$NaB{H_4}$
D
$Zn / HCl$

Answer

Correct option: B.

$AlC{l_3}$

b
(b) $\mathop {C{H_3}C{H_2}C{H_2}C{H_3}}\limits_{n - {\rm{butane}}} \xrightarrow[\Delta]{Anhyd AlCl_3} \mathop {C{H_3} - \mathop {CH}\limits_{\mathop {|\,\,\,\,\,}\limits_{\,\,C{H_3}} } - C{H_3}}\limits_{{\rm{iso}}\,{\rm{butane}}} $

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MCQ 4931 Mark

Aluminium carbide on reacting with water gives

✓
Methane
B
Ethane
C
Ethene
D
Ethyne

Answer

Correct option: A.

Methane

a
(a) $A{l_4}{C_3} + 6{H_2}O \to \mathop {3C{H_4}}\limits_{{\rm{Methane}}} + 2A{l_2}{O_3}$

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MCQ 4941 Mark

The marsh gas detector used by minerals works on the principle of

✓
Difference in the rates of diffusion of gases
B
Avogadro's hypothesis
C
Gay-Lussac's law of gaseous volumes
D
Berzelius hypothesis

Answer

Correct option: A.

Difference in the rates of diffusion of gases

a
The marsh gas detector used by miners works on the principle of Difference in the rates of diffusion of gases.

A marsh gas detector is a device that detects the presence of gases in an area, often as part of a safety system. This type of equipment is used to detect a gas leak or other emissions and can interface with a control system so a process can be automatically shut down. This type of device is important because there are many gases that can be harmful to organic life, such as humans or animals.

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MCQ 4951 Mark

Octane number can be changed by

A
Isomerisation
B
Alkylation
C
Cyclisation
✓
All of these

Answer

Correct option: D.

All of these

d
(d) The octane numbers of Fuel can be improved by increasing the percentage of branched chain alkanes, alkenes and aromatic hydrocarbon. Thus octane number can be changed by isomerisation (reforming), alkylation and aromatisation (cyclisation) etc.

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MCQ 4961 Mark

Gasoline has composition

A
${C_8} - {C_{12}}$
B
${C_2} - {C_5}$
✓
${C_6} - {C_{11}}$
D
None of these

Answer

Correct option: C.

${C_6} - {C_{11}}$

c
(c) The approximate composition of gasoline is ${C_6} - {C_{11}}$ at boiling point $70-200\,^oC$ and is used in motor fuel, dry cleaning, petrol gas etc.

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MCQ 4971 Mark

The complete combustion of $C{H_4}$ gives

A
$CO + {H_2}$
B
$CO + {N_2}$
✓
$C{O_2} + {H_2}O$
D
$CO + {N_2}O$

Answer

Correct option: C.

$C{O_2} + {H_2}O$

c
(c) $C{H_4} + {O_2} \to C{O_2} + 2{H_2}O$

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MCQ 4981 Mark

Which one of the following compounds gives methane on treatment with water

✓
$A{l_4}{C_3}$
B
$Ca{C_2}$
C
$VC$
D
$SiC$(e)${B_4}C$

Answer

Correct option: A.

$A{l_4}{C_3}$

a
(a) $A{l_4}{C_3} + 12{H_2}O \to 3C{H_4} + 4Al{(OH)_3}$

$Ca{C_2} + 2{H_2}O \to {C_2}{H_2} + Ca{(OH)_2}$

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MCQ 4991 Mark

Pick out the alkane which differs from the other members of the group.

A
$2,2-$dimethyl propane
B
Pentane
C
$2-$methyl butane
✓
$2,2-$dimethyl butane

Answer

Correct option: D.

$2,2-$dimethyl butane

d
(d) Except $2,2$ dimethyl butane rest compound contain $5$ carbon i.e., pantane while $2,2 $ dimethyl butane contain $6$ carbon i.e., Hexane

$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3} - C{H_2} - C - C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$

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MCQ 5001 Mark

The product obtained on reaction of ${C_2}{H_5}Cl$ with hydrogen over palladium carbon is

A
${C_3}{H_8}$
B
${C_4}{H_{10}}$
✓
${C_2}{H_6}$
D
${C_2}{H_4}$

Answer

Correct option: C.

${C_2}{H_6}$

c
(c) ${C_2}{H_5}Cl + {H_2} \xrightarrow{Pd/c} {C_2}{H_6} + HCl$

This reaction is used for the preparation of pure alkanes.

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