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1. Find out the total number of voids in 0.5 mole of<br />
a <strong>com</strong>pound forming hexagonal closed packed<br />
structure.<br />
(a) 9.034 × 10 23 (b) 6.023 × 10 23<br />
(c) 18.069 × 10 23 (d) 3.011 × 10 23<br />
2. How much energy will be required to ionise 1 mole<br />
of hydrogen atoms?<br />
(a) 1350 kJ<br />
(b) 1350 J<br />
(c) 1312 kJ<br />
(d) 1312 J<br />
3. A 1 and A 2 are two ores of metal ‘M’.<br />
A 1 on calcination gives black precipitate, CO 2 and<br />
H 2 O.<br />
Calcination<br />
A 1<br />
Black ppt. + CO<br />
2<br />
+ H2O<br />
While A 2 on roasting gives metal and a gas.<br />
A Roasting<br />
2 Metal + Gas<br />
KCrO + H SO<br />
2 2 7 2 4<br />
Gas P(Green coloured)<br />
In the given sequence, A 1 and A 2 respectively are<br />
(a) CuCO 3 and Cu 2 S<br />
(b) CuCO 3 . Cu(OH) 2 and Cu 2 S<br />
(c) CuCO 3 and Cu 2 O<br />
(d) CuCO 3 . Cu(OH) 2 and Cu 2 O<br />
4. The values of observed and calculated molecular<br />
weights of silver nitrate are 92.64 and 170<br />
respectively. The degree of dissociation of silver<br />
nitrate will be<br />
(a) 52.8% (b) 83.5% (c) 46.7% (d) 60.2%<br />
5. The total number of gas molecules in a room of<br />
capacity 25 m 3 at a temperature of 27°C and 1 atm<br />
pressure will be<br />
(a) 3.011 × 10 23 (b) 6.119 × 10 23<br />
(c) 6.119 × 10 26 (d) 3.011 × 10 26<br />
6. CaO and NaCl have the same crystal structure and<br />
approximately the same ionic radii. If U is the lattice<br />
energy of NaCl, the approximate lattice energy of<br />
CaO is<br />
May <strong>2017</strong><br />
(a) U (b) U (c) 2U (d) 4U<br />
2<br />
7. ‘925 fine silver’ means<br />
(a) 9.5% Ag + 90.5% Cu<br />
(b) 92.5% Ag + 7.5% Cu<br />
(c) 9.25% Cu + 90.75% Ag<br />
(d) 7.5% Ag + 92.5% Cu<br />
8. What is the product formed when the following<br />
reaction takes place?<br />
HgSO 4/H2SO4<br />
C CH<br />
DO 2<br />
(a) CD 2 CHO<br />
(b) CO CHD 2<br />
(c) CO CH 2<br />
D<br />
(d) C(OD) CHD<br />
9. The entropy change can be calculated by using the<br />
expression, ∆S = q rev . When water freezes in a<br />
T<br />
glass beaker what happens?<br />
(a) ∆S(system) decreases but ∆S(surroundings)<br />
remains the same.<br />
(b) ∆S(system) increases but ∆S(surroundings)<br />
decreases.<br />
(c) ∆S(system) decreases but ∆S(surroundings)<br />
increases.<br />
(d) ∆S(system) and ∆S(surroundings) both decrease.<br />
10. Under which of the following reaction conditions,<br />
aniline gives p-nitro derivative as the major<br />
product?<br />
(a) Acetyl chloride/pyridine followed by reaction<br />
with conc. H 2 SO 4 + conc. HNO 3<br />
(b) Ethyl alcohol/pyridine followed by conc. H 2 SO 4<br />
+ conc. HNO 3<br />
CHEMISTRY TODAY | APRIL ‘17 31
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