M.C.Q [1M]

MCQ 11 Mark

DNA fingerprinting means the

A
sequencing the nucleotides in DNA
B
sequencing the bases present in double helix
✓
information regarding the unique sequence of bases on DNA for a person
D
information reagrding the unique imprints on the fingertip for a person

Answer

Correct option: C.

information regarding the unique sequence of bases on DNA for a person

(c) information regarding the unique sequence of bases on DNA for a person
Explanation: A sequence of bases on DNA is unique for a person and information regarding this is called DNA fingerprinting. It is same for every cell and cannot be altered by any known treatment.

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MCQ 21 Mark

Match the items of column I with appropriate entries of column II.

Column I	Column II
(a) $\frac{\Delta P }{ P ^{\circ}{ }_A}$	(i) $\frac{\Delta T _{ b }}{ m }$
(b) K_b	(ii) mol fraction of solute
(c) i	(iii) $\frac{\Delta T _{ f }}{ m }$
(d) K_f	(iv) Ratio of observed molar mass to actual molar mass

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

Answer

Correct option: A.

(a) (ii), (b) - (i), (c) - (iv), (d) - (iii)

(a) (a)-(ii), (b) - (i), (c) - (iv), (d) - (iii)
Explanation: (a) - (ii), (b) - (i), (c) - (iv), (d) - (iii)

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MCQ 31 Mark

The slope of the line in the plot of concentration [A] Vs. time (s) indicate

A
$+ k$
✓
$- k$
C
$\frac{+k}{2.303}$
D
$\frac{-k}{2.303}$

Answer

Correct option: B.

$- k$

(b) -k
Explanation: Slop of the line indicates = -k while the intercept represents [R]0.

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MCQ 41 Mark

Carbon tetrachloride has a dipole moment:

✓
$\mu=0$
B
$\mu=1$
C
$\mu=2$
D
$\mu=4$

Answer

Correct option: A.

$\mu=0$

(a) μ = 0
Explanation: CCl₄ is a symmetrical molecule. Hence, the dipole moment is zero.

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MCQ 51 Mark

If 75% of a first order reaction was completed in 32 min, then 50% of the reaction was completed in _______ .

A
24 min
B
4 min
✓
16 min
D
8 min

Answer

Correct option: C.

16 min

(c) 16 min
Explanation: 75% completion means 2 half lifes so 50% completion means only one half life.
$\begin{array}{l}k=\frac{2.303}{t} \log \frac{a}{a-x} \\ k=\frac{2.303}{32} \log \left(\frac{100}{100-75}\right) \ldots(1) \\ k=\frac{2.303}{t} \log \left(\frac{100}{100-50}\right) \ldots(2)\end{array}$
from (1) and (2), we get
t = 16 mins

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MCQ 61 Mark

Among the following, which bivalent ion of the first transition series shows a maximum magnetic moment?

A
Co²⁺
B
Ni²⁺
✓
Mn²⁺
D
Fe²⁺

Answer

Correct option: C.

Mn²⁺

(c) Mn²⁺
Explanation: Mn²⁺ has d⁵ configuration so a maximum number of unpaired electrons and hence maximum magnetic moment. This magnetic moment can be calculated by using the spin only formula: µ_so = ∠n(n+2), where n= number of unpaired electrons.

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MCQ 71 Mark

The order of reactivity of following alcohols with halogen acids is ______.

A
(A) > (C) > (B)
✓
(C) > (B) > (A)
C
(B) > (A) > (C)
D
(A) > (B) > (C)

Answer

Correct option: B.

(b) (C) > (B) > (A)
Explanation: Haloalkanes are prepared from alcohol and halogen acids where the hydroxyl group of the alcohol is replaced by the halogen. Options (A) (B) and (C) are primary, secondary, tertiary alcohols respectively. Tertiary alcohols are more reactive than secondary and primary alcohol, the secondary halide is more reactive than primary halide and they form haloalkanes from haloacids at room temperature without catalysts. The order of reactivity of alcohols is 3°>2°>1°.

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MCQ 81 Mark

Give IUPAC name of the compound given below.

A
2-Chloro-5-hydroxyhexane
B
5-Chlorohexan - 2 - ol
C
2-Hydroxy-5-chlorohexane
✓
2-Chlorohexan - 5 - ol

Answer

Correct option: D.

2-Chlorohexan - 5 - ol

(d) II < I < III

Electron withdrawing group decreases the basic strength of aniline while electron releasing groups increases the basic strength of aniline.

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MCQ 91 Mark

The common name for pentanedioic acid is:

A
Succinic acid
B
Pimelic acid
C
Oxalic acid
✓
Glutaric acid

Answer

Correct option: D.

Glutaric acid

(d) Glutaric acid
Explanation:
→ Pentanedioic acid is known as glutaric acid.
→ (COOH)_{2 is known as oxalic acid.
→ Butanedioic acid is known as succinic acid.
→ Hexanedioic acid is known as adipic acid.
→ Heptanedioic acid is known as pimelic acid.}

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MCQ 101 Mark

How to do the following conversion:
RCOOCI + ? → RCHO

✓
Using H₂-Pd, BaSO₄
B
Using DIBAL-H
C
Using H₂ - Pd
D
Using NaBH₄

Answer

Correct option: A.

Using H₂-Pd, BaSO₄

(a) Using H₂-Pd, BaSO₄
Explanation: Catalytic hydrogenation of acid chloride using H₂-Pd, BaSO₄ converts acid chloride selectively to aldehydes (BaSO₄ reduces the activity of palladium). This is known as Rosenmund Reduction.

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MCQ 111 Mark

One mole of an organic compound 'A' with the formula C₃H₈O reacts completely with two moles of HI to form X and Y. When 'Y' is boiled with aqueous alkali forms Z. Z answers the iodoform test. The compound 'A' is ________