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(c) Dil. HCl followed by reaction with conc. H 2 SO 4<br />
+ conc. HNO 3<br />
(d) Reaction with conc. HNO 3 + conc. H 2 SO 4<br />
11. Which of the following statements is not true?<br />
(a) Nascent hydrogen can be produced even at<br />
room temperature but atomic hydrogen is<br />
produced at elevated temperature.<br />
(b) Nascent hydrogen can never be isolated but<br />
atomic hydrogen can be isolated.<br />
(c) Reducing power of atomic hydrogen is much<br />
less than that of nascent hydrogen.<br />
(d) Both nascent and atomic hydrogen are more<br />
reactive than ordinary hydrogen.<br />
12. Amongst TiF 2– 6 , CoF 3– 6 , Cu 2 Cl 2 and NiCl 2– 4 , the<br />
colourless species are<br />
(a) CoF 3– 2–<br />
6 and NiCl 4 (b) TiF 2– 3–<br />
6 and CoF 6<br />
2–<br />
(c) Cu 2 Cl 2 and NiCl 4 (d) TiF 2– 6 and Cu 2 Cl 2<br />
13. The values of K sp of two sparingly soluble salts<br />
Ni(OH) 2 and AgCN are 2 × 10 –15 and 6 × 10 –17<br />
respectively. Which salt is more soluble?<br />
(a) Ni(OH) 2<br />
(b) AgCN<br />
(c) Both are equally soluble.<br />
(d) Cannot be predicted.<br />
14. In the following sequence of reactions :<br />
+ HOCl<br />
Identify D.<br />
NH 2<br />
(a)<br />
F<br />
H +<br />
A<br />
NaNH / 2<br />
liq. NH 3<br />
B HBF 4<br />
(b)<br />
+<br />
NBF<br />
2 4 –<br />
Cl<br />
C<br />
NaNO 2<br />
D<br />
16. A cylinder of gas is assumed to contain 11.2 kg of<br />
butane (C 4 H 10 ). If a normal family needs 20,000 kJ<br />
of energy per day, the cylinder will last in<br />
(Given : ∆H for <strong>com</strong>bustion of butane is – 2658 kJ)<br />
(a) 20 days<br />
(b) 22 days<br />
(c) 26 days<br />
(d) 24 days.<br />
17. An electric current is passed through an aqueous<br />
solution of a mixture of alanine (isoelectric point<br />
6.0), glutamic acid (3.2) and arginine (10.7) buffered<br />
at pH 6. What is the fate of the three acids?<br />
(a) Glutamic acid migrates to anode at pH 6.<br />
Arginine present as a cation and migrates to<br />
the cathode. Alanine as a dipolar ion remains<br />
uniformly distributed in solution.<br />
(b) Glutamic acid migrates to cathode and others<br />
remain uniformly distributed in solution.<br />
(c) All these remain uniformly distributed in<br />
solution.<br />
(d) All three move to cathode.<br />
18. Oxidation states of X, Y, Z are +2, +5 and –2<br />
respectively. Formula of the <strong>com</strong>pound formed will<br />
be<br />
(a) X 2 YZ 6 (b) XY 2 Z 6<br />
(c) XY 5 Z 2 (d) X 3 YZ 4<br />
19. Half-life time of a radioactive element X is same as<br />
the mean life time of another radioactive element Y.<br />
Initially both of them have same number of atoms,<br />
then<br />
(a) X and Y have the same decay rate initially<br />
(b) X and Y have the same decay rate always<br />
(c) Y will decay at faster rate than X<br />
(d) X will decay at faster rate than Y.<br />
20. Consider the following sequence of reactions :<br />
( A)<br />
(i) Br /Fe 2<br />
(ii) Mg/ether<br />
Identify E.<br />
CH2OH<br />
( B)<br />
CH 2 O<br />
( C)<br />
HO+<br />
3<br />
( )<br />
OH<br />
Cl /Fe 2<br />
Jone’s reagent<br />
( D)<br />
(c)<br />
(d)<br />
(a)<br />
(b)<br />
15. Aniline is diazotised and the diazonium salt<br />
hydrolysed to yield phenol which is brominated to<br />
produce C 6 H 2 (Br 3 )OH. Calculate the mass of the<br />
final product obtained from 9.3 g of aniline if the<br />
yield in the two steps is 45% and 70% respectively.<br />
(Atomic mass of Br = 80)<br />
(a) 1.04 g (b) 10.43 g (c) 14.89 g (d) 23.17 g<br />
(c)<br />
Cl<br />
CHO<br />
Cl<br />
(d)<br />
Cl<br />
O<br />
C<br />
Cl<br />
CH 3<br />
32 CHEMISTRY TODAY | APRIL ‘17
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