Sample QuestionsModel Paper 7 questions
One sample from each question group in this chapter. Select any group above to see the full set with answer keys.
On the basis of thermochemical equations (A), (B) and (C), find out which of the algebraic relationships given in options (i) to (iv) is correct:
A. C(graphite) $+ O _2(g) \rightarrow CO _2$ (g); $\triangle_r H= x KJ mol ^{-1}$
B. C(graphite) $+\frac{1}{2} O_2(g) \rightarrow C O(g) ; \Delta_r H= y KJ mol ^{-1}$
C. $C O(g)+\frac{1}{2} O_2(g) \rightarrow C O_2(g) ; \Delta_r H=z k J m o l=1$
- ✓
$x=y+z$
- B
$y=2 z-x$
- C
$z=x+y$
- D
$x=y-z$
Answer: A.
View full solution →The following compounds do not show ketoenol tautomerism, except:
Answer: B.
View full solution →In an atom, the maximum number of electrons in an orbit / principal energy level n is
- ✓
$2 n^2$
- B
$2 n$
- C
$2 n -1$
- D
$n^2$
Answer: A.
View full solution →A person is suffering with fever with a high temperature of $104^{\circ} F$. What will be his body temperature in ${ }^{\circ} C$ ?
- A
$32.38{ }^{\circ} C$
- B
$28.10^{\circ} C$
- C
$18.68^{\circ} C$
- ✓
$40^{\circ} C$
Answer: D.
View full solution →The hydrocarbon which can react with sodium in liquid ammonia is ____________________ .
- A
$CH _3 CH = CHCH _3$
- ✓
$CH _3 CH _2 C \equiv CH$
- C
$CH _3 CH _2 CH _2 C \equiv CCH _2 CH _2 CH _3$
- D
$CH _3 CH _2 C \equiv CCH _2 CH _3$
Answer: B.
View full solution →What kind of information about an electron in an atom is obtained from its wave function?
Write a short note on hydrogenation of unsaturated aliphatic hydrocarbons.
Hydrocarbon A (molecular formula is $C _5 H _8$ ) gave a white precipitate with ammoniacal silver nitrate. Oxidation of A with hot alkaline $KMnO _4$ gave 2-methyl propanoic acid. What is the structural formula of A?
View full solution →What will be the mass of one ${ }^{12} C$ atom in g ?
View full solution →1. How do the electronic configurations of the elements with $Z =107-109$ differ from one another?
2. $Rn ( Z =86)$ is the last noble gas discovered. Predict what will be the atomic number of the next noble gas to be discovered. Write its symbol.
View full solution →On the basis of VSEPR theory, predict the shapes of the following
1. $NH _2^{-}$
2. $O _3$
View full solution →1. Calculate the gram molecular mass of sugar having molecular formula $C _{12} H _{22} O _{11}$.
2. Calculate
a. The mass of 0.5 g molecule of sugar and
b. Gram molecule of sugar in 547.2 g .
View full solution →Describe the theory associated with the radius of an atom as it:
1. gains an electron
2. loses an electron
In a hydrogen atom, the energy of an electron in first Bohr's orbit is $E _{ n }=-\frac{2 \pi^2 me ^4}{ n ^2 h^2}$.
What is the energy required for its excitation to Bohr's second orbit?
View full solution →Consider the reactions :
a. $6 CO _2(g)+6 H _2 O ( I ) \longrightarrow C _6 H _{12} O _6( aq )+6 O _2$ (g)
b. $O _3(g)+ H _2 O _2( I ) \longrightarrow H _2 O ( I )+2 O _2(g)$
Why it is more appropriate to write these reactions as :
a. $6 CO _2+12 H _2 O ( I ) \longrightarrow C _6 H _{12} O _6( aq )+6 H _2 O ( I )+6 O _2(g)$
b. $O _3(g)+ H _2 O _2( I ) \longrightarrow H _2 O ( I )+ O _2(g)+ O _2(g)$
Also suggest a technique to investigate the path of the above (a) and (b) redox reactions.
View full solution →At 1127 K and 1 atmosphere pressure, a gaseous mixture of CO and $CO _2$ in equilibrium with solid carbon has 90.55\% CO by mass.
$
C(s)+CO_2(g) \rightleftharpoons 2 CO(g)
$
Calculate $K _{ C }$ for the reaction at the above temperature.
View full solution →Attempt any five of the following:
1. Why does the iodination of benzene is carried out in the presence of nitric acid or iodic acid?
2. Can a catalyst change the position of equilibrium in a reaction?
3. Why is benzene extraordinarily stable though it contains three double bonds?
4. Bring out the following conversion ethane to ethene.
5. Why are alkanes called paraffins?
6. Draw the New man's projection formula of the staggered form of 1,2-dichloroethane.
7. Give the IUPAC name of the lowest molecular weight alkane that contains a quaternary carbon.
1. What are electrophiles and nucleophiles? Explain with examples.
2. Derive the structure of 3 - Nitrocyclohexene.
1. What is the general molecular formula of saturated monohydric alcohols?
2. Write structural formulae for compounds named as-
a. 1-Bromoheptane
b. 5-Bromoheptanoic acid
Reaction between $N _2$ and $O _2$ - takes place as follows:
$
2 N_2(g)+O_3(g) \rightleftharpoons 2 N_2 O(g)
$
If a mixture of 0.482 mol of $N _2$ and 0.933 mol of $O _2$ is placed in a 10 L reaction vessel and allowed to form $N _2 O$ at a temperature for which $K_c=2.0 \times 10^{-37}$ determines the composition of the equilibrium mixture.
View full solution →Assertion (A): Each side of a cube is measured to be 7.203 m . What is the volume of the cube to appropriate significant figure $373.7 m^3$.
Reason (R): The mass of one mole of a substance in grams is called its average atomic mass.
- A
Both A and R are true and R is the correct explanation of A.
- B
Both A and R are true but R is not the correct explanation of A.
- ✓
A is true but R is false.
- D
A is false but R is true.
Answer: C.
View full solution →Assertion (A): Hydrogen atom has only one electron in its orbit. But it produces several spectral lines.
Reason (R): There are many excited energy levels available.
- ✓
Both A and R are true and R is the correct explanation of A.
- B
Both A and R are true but R is not the correct explanation of A.
- C
A is true but R is false.
- D
A is false but R is true.
Answer: A.
View full solution →Assertion (A): Same number of electron pairs are present in resonance structures.
Reason (R): Resonance structures differ in the location of electrons around the constituent atoms.
- ✓
Both A and R are true and R is the correct explanation of A.
- B
Both A and R are true but R is not the correct explanation of A.
- C
A is true but R is false.
- D
A is false but R is true.
Answer: A.
View full solution →Assertion (A): The presence of $Ag ^{+}$enhances the solubility of alkenes in water.
Reason (R): Alkenes are weakly polar in nature.
- A
Both A and R are true and R is the correct explanation of A.
- ✓
Both A and R are true but R is not the correct explanation of A.
- C
A is true but R is false.
- D
A is false but R is true.
Answer: B.
View full solution →The ionic character of metallic halides tends toward covalent nature as per Fajan's rule. Such covalent halides behave as non-metal in their higher oxidation states. The property to hydrolyse to give oxy-acids of the element and corresponding hydro halogen acid for most non-metallic elements proceeds exceptionally in the way, keeping oxidation number of element and halide sam in oxo-acids.
Non-polar halides are immiscible in water, as they do not show hydrolysis, but halides of some elements with empty d-orbital undergo hydrolysis. Stability of halides of the higher state is governed by the inert-pair effect.
1. How does halide undergo hydrolysis to give oxy-acids of underlined element $PCl _3$ ? (1)
2. Out of $NCl _3$ and $BCl _3$ undergoes hydrolysis to form oxy-acids? Write the chemical reaction for the correct answer. (1)
3. Out of $PbCl _4, PbF _4, PbI _4$ and $PbBr _4$ which one doesn't exist? (2)
OR
Non-Polar halides are immiscible in water. Why? (2)
View full solution →IUPAC (International Union of Pure and Applied Chemistry) system of nomenclature. Common names are useful and in many cases indispensable, particularly when the alternative systematic names are lengthy and complicated. A systematic name of an organic compound is generally derived by identifying the parent hydrocarbon and the functional group(s) attached to it. By using prefixes and suffixes, the parent name can be modified to obtain the actual name. In a branched-chain compound, small chains of carbon atoms are attached at one or more carbon atoms of the parent chain. The small carbon chains (branches) are called alkyl groups. An alkyl group is derived from a saturated hydrocarbon by removing a hydrogen atom from carbon. Abbreviations are used for some alkyl groups. For example, methyl is abbreviated as Me, ethyl as Et, propyl as Pr and butyl as Bu.
1. Draw the structure of 3-Ethyl-4,4-dimethylheptane. (1)
2. How is the numbering in branched chain hydrocarbon done?
3. Derive the structure of 2-Chlorohexane. (2)
OR
Why $CH _4$ after becoming- $CH _3$ called a methyl group? (2)
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