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(a) 983 (b) 710
(c) 596 (d) 1133
O
25. The diketone HC 3
C (CH
22
) C CH 3
on intramolecular aldol condensation gives the
product
O
O
(a)
(b)
CH 3
O
O
OH
(c)
(d)
CH 3
CH 3
26. An iron cylinder contains helium at a pressure of
250 kPa at 300 K. The cylinder can withstand a
pressure of 1 × 10 6 Pa. The room in which cylinder
is placed catches fire. If the melting point of cylinder
is 1800 K, then the minimum temperature at which
cylinder will burst is
(a) 800 K
(b) 1200 K
(c) 1800 K
(d) will not burst.
27. Consider the following sequence for extraction of Ag :
(Ag + Pb) alloy Melt and
→ (Ag + Pb + Zn) melt
zinc is added
Cool
→
Layer X
→
Layer Y
Select the correct statement.
(a) Layer X contains Zn and Ag.
(b) Layer Y contains Pb and Ag but amount of Ag
in this layer is smaller than in layer X.
(c) X and Y are immiscible layers.
(d) All are correct statements.
28. Which of the following is called Sandmeyer
reaction?
NaOH
(a) 2HCHO CH3 OH + HCOONa
(b)
(c)
+ CH Cl
3
CuCl/HCl
AlCl 3
CH 3
OH CO
CH
2 3
(d)
NaOH
COOH
29. The hypothetical complex triamminediaquachloro
cobalt(III) chloride can be represented as
(a) [Co(NH 3 ) 3 (H 2 O) 2 Cl]Cl 2
(b) [Co(NH 3 ) 3 (H 2 O)Cl 3 ]
O
(c) [Co(NH 3 ) 3 (H 2 O) 2 Cl]
(d) [Co(NH 3 ) 3 (H 2 O) 3 ]Cl 3
30. For the given sequence of reaction :
Br2 / Red P alc.
NH3
CH 3 CH 2 COOH →( A) →( B)
∆
the final product (B) will be
(a) alanine
(b) pyruvic acid
(c) citric acid (d) lactic acid.
31. Phenol associates in benzene to a certain extent to
form a dimer. A solution containing 20 × 10 –3 kg
of phenol in 1.0 kg of benzene has its freezing
point depressed by 0.69 K. Calculate the fraction of
phenol dimerised. (K f for C 6 H 6 = 5.12 K mol –1 kg)
(a) 73.4% (b) 63.3%
(c) 36.7% (d) 26.6%
32. During the process of digestion, the proteins
present in food materials are hydrolysed to amino
acids. The two enzymes involved in the process,
A
Polypeptides Enzyme ( B)
Proteins Enzyme ( )
Amino acids
A and B respectively are
(a) pepsin and trypsin (b) invertase and zymase
(c) amylase and maltase (d) diastase and lipase.
33. An optically active amine (C 5 H 13 N) on treatment
with aq. NaNO 2 /HCl forms an optically inactive
alcohol (C 5 H 12 O) with evolution of N 2 gas.
The amine is
(a) 1-pentanamine (b) 2-pentanamine
(c) 3-pentanamine (d) 2-methylbutanamine.
34. The IUPAC name of is
(a) 4,4-dimethyl-5-5diethylpentane
(b) 5,5-diethyl-4,4-dimethylpentane
(c) 3-ethyl-4,4-dimethylheptane
(d) 1,1-diethyl-2,2-dimethylpentane.
35. Calculate the entropy change when 1 kg of water is
heated from 27°C to 200°C forming super-heated
steam under constant pressure. Given : specific
heat of water = 4180 J/kg - K and specific heat of
steam = 1670 + 0.49 T J/kg - K (where T is absolute
temperature) and latent heat of vaporisation
= 23 × 10 5 J/kg.
(a) 7522.5 J
(b) 75.22 J
(c) 7.522 J
(d) 445.2 J
36. A compound of vanadium has a magnetic moment of
1.73 BM. Choose the correct electronic configuration
of the vanadium ion in the compound.
CHEMISTRY TODAY | APRIL ‘17 41