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(a) 1s 2 , 2s 2 2p 6 , 3s 2 3p 6 3d 2
(b) 1s 2 , 2s 2 2p 6 , 3s 2 3p 6 3d 3
(c) 1s 2 , 2s 2 2p 6 , 3s 2 3p 6 3d 1
(d) 1s 2 , 2s 2 2p 6 , 3s 2 3p 6 3d 0
37. Given the polymers,
A = Nylon–6, 6; B = Buna-S; C = Polythene.
Arrange these in increasing order of their
intermolecular forces (lower to higher).
(a) A < B < C (b) C < A < B
(c) B < C < A (d) A < C < B
38. In the following reaction,
CH 3
HC 3 C CH CH 2
CH 3
The major product is
CH 3
(a) HC 3 C CH CH 3
OH CH 3
+ H2O/H
CH 3
(b) CH 2 C CH 2
CH 3
OH
CH 3
CH 3
(c) HC 3 C CH CH 3
CH 3 OH
CH 3
(d) HC 3 C CH 2
CH 2
A
Major
product
+
B
Minor
product
CH 3 OH
39. For the preparation of a detergent ‘A’ from benzene,
the following steps are involved :
I.
III.
s
These steps should be in sequence
(a) I, II, III
(b) II, I, III
(c) II, III, I
(d) I, III, II
40. Observe the graph and identify the correct
statement.
II.
(a) T 1 is melting point, T 2 is boiling point.
(b) T 1 is boiling point, T 2 is melting point.
(c) ∆S fus is more than ∆S vap.
(d) T 2 is lower than T 1 .
ASSERTION AND REASON
Directions : In the following questions (41-60), a statement
of assertion is followed by a statement of reason. Mark the
correct choice as :
(a) If both assertion and reason are true and reason is the
correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the
correct explanation of assertion.
(c) If assertion is true but reason is false.
(d) If both assertion and reason are false.
41. Assertion : Standard heat enthalpy of diamond is
taken as zero.
Reason : In most stable forms, the standard enthalpy
of formation is taken as zero.
42. Assertion : Melting point of neopentane is higher
than that of n-pentane but the boiling point of
n-pentane is higher than that of neopentane.
Reason : Melting point depends upon packing of
molecules in the crystal lattice while boiling point
depends upon surface area of the molecule.
43. Assertion : But-1-ene and 2-methylprop-1-ene are
position isomers.
Reason : Position isomers have same molecular
formula but different arrangement of carbon atoms.
44. Assertion : p-Chlorobenzoic acid is stronger than
benzoic acid.
Reason : Chlorine has electron donating resonance
(+R)-effect.
45. Assertion : The micelle formed by sodium stearate
in water has –COO – groups at the surface.
Reason : Surface tension of water is reduced by the
addition of stearate.
46. Assertion : A solution of sucrose in water is
dextrorotatory but on hydrolysis in presence of
little hydrochloric acid, it becomes laevorotatory.
Reason : Sucrose on hydrolysis gives unequal
amounts of glucose and fructose as a result of which
change in sign of rotation is observed.
42 CHEMISTRY TODAY | APRIL ‘17