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Class- 12 th
CHEMISTRY
Solutions
1. Homogeneous mixture of two or more than two
components is called;
(1) Solute (2) Solvent
(3) Both (1) & (2) (4) Solution
2. The Van't Hoff factor (i) for a dilute solution of
K [Fe(CN) ] 3 6 is:
3. A solution is prepared by adding 5 g of a substance
(x) to 18 g of water. Calculate the mass percentage
of the solute?
(1) 21.74% (2) 19%
4. Van't Hoff factor of Hg 2 Cl 2 in its aqueous solution
will be (Hg 2 Cl 2 is 80% ionized in the solution):
(1) 1.6 (2) 2.
5. Which one of the following is not a true solution?
(1) Amalgam (2) Ornamental gold
(3) Salt water (4) Milk
6. Molarity is expressed as:
(1) mol/L-atm (2) mol/L
(3) mol/1000 g (4) g/L
7. Molarity of a given orthophosphoric acid solution is
3 M. It’s normality is:
(1) 9 N (2) 0.3 N
(3) 3 N (4) 1 N
8. Henry’s law constant for molality of methane in
benzene at 298 K is 4.27 × 10
5 mm Hg. The mole
fraction of methane in benzene at 298 K under 760
mm Hg is:
(1) 1.78 × 10
9. H 2 S is a toxic gas used in qualitative analysis. If
solubility of H 2 S in water at STP is 0.195m, what is
the value of KH?
(1) 0.0263 bar
(2) 69.16 bar
(3) 192 bar
(4) 282 bar
10. Which of the following concentration factors is
affected by change in temperature?
(1) Molarity
(2) Molality
(3) Mole fraction
(4) Weight fraction
11. An aqueous solution of methanol in water has
vapour pressure:
(1) Equal to that of water
(2) Equal to that of methanol
(3) More than that of water
(4) Less than that of water
12. What will be the molality of a solution having 18 g
glucose (mol. wt. = 180) is dissolved in 500 g of
water?
(1) 1 m
(2) 0.5 m
(3) 0.2 m
(4) 2 m
13. Which of the following statement is true for
aqueous solution of 0.1 M urea, 0.2M glucose and
0.3M sucrose?
(1) The vapour pressure and freezing point are the
lowest for urea.
(2) The Osmotic pressure and boiling point are the
lowest for urea.
(3) The depression in freezing point is the highest
for urea.
(4) The elevation in boiling point is the highest for
urea.
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14. Which one of the following is not correct for an
ideal solution?
(1) It must obey Raoult’s law
(2) H (^) mix = 0
(3) V (^) mix = 0
(4) H (^) mix = V (^) mix 0
15. The vapour pressure of pure CHCl 3 and CH 2 Cl 2 are
200 and 41.5 atm respectively. The weight of CHCl 3
and CH 2 Cl 2 are 11.9 g and 17 g respectively in a
solution. The vapour pressure of solution (in atm)
will be:
16. An ideal solution is that which:
(1) Obey Raoult’s law
(2) Shows positive deviation from Raoult’s law
(3) Shows negative deviation from Raoult’s law
(4) Has no connection with Raoult’s law
17. Elevation in boiling point was 0.52 C when 6 g of a
compound X was dissolved in 100 g of water.
Molecular weight of X is (Kb = 0.52 k kg mol
(1) 120 (2) 60
18. Which one is a colligative property?
(1) Boiling point
(2) Vapour pressure
(3) Osmotic pressure
(4) Freezing point
19. If 0.15g of a solute dissolved in 15g of solvent is
boiled at a temperature higher by 0.216°C than that
of the pure solvent. The molecular weight of the
substance (molal elevation constant for the solvent
is 2.16°C kg mol
(1) 1.01 g/mol
(2) 10 g/mol
(3) 10.1 g/mol
(4) 100 g/mol
20. Calculate the mole percentage of CH 3 OH and H 2 O
respectively in 60 % (by mass) aqueous solution of
CH 3 OH?
21. The osmotic pressure of a solution containing 1.
g of sucrose (mol. wt. 348) dissolved to make a litre
of solution at 27°C (R = 0.082 L atm K–^1 mol–^1 ) is:
22. Find the percentage by mass and mass fraction of
insulin in the solution prepared by dissolving 4.48g
of insulin in 26.52g of water.
(1) 0.125 (2) 0.
23. For an aqueous solution, freezing point is – 0.186°C.
Elevation of boiling point of the same solution is;
(1) 0.186ºC (2) 0.052ºC
(3) 1.86ºC (4) 5.12ºC
24. Azeotropic mixture of HCl and water has:
(1) 48% HCl
(2) 22.2% HCl
(3) 36% HCl
(4) 20.2% HCl
25. Which of the following mixture does not show
positive deviation from the Raoult’s law?
(1) Benzene + acetone
(2) Acetone + ethanol
(3) Acetone + chloroform
(4) Water + ethanol
26. The value of Henry’s law constant for some gases at
293 K is given below. Arrange the gases in the
increasing order of their solubility.
He : 144.97 kbar, H 2 : 69.16 kbar,
N 2 : 76.48 kbar, O 2 : 34.86 kbar
(1) He < N 2 < H 2 < O 2
(2) O 2 < H 2 < N 2 < He
(3) H 2 < N 2 < O 2 < He
(4) He < O 2 < N 2 < H 2
27. In amalgam of mercury with sodium, solvent is;
(1) Mercury (2) Sodium
(3) Amalgam (4) None of these
28. Determine the volume percent of solution made by
containing 25 mL of ethanol with enough water to
produce 200 mL of the solution:
(1) 12.5 (2) 20
41. Liquid benzene freezes at 7ºC and boils at 77ºC. If
the Kf and Kb values for benzene are 5.0 K-Kg/mol
and 2.50 K-Kg/mol respectively, calculate the ratio
of the molar latent heat of fusion to the molar latent
heat of vaporisation.
( 1 ) 3.125 ( 2 ) 0.
42. Scuba divers when go in deep sea face a very painful
situation known as "bends", the formation of N 2
bubbles around the joints due to decrease in
solubility of N 2 as a result of reduced pressure, when
the diver rises up towards sea surface. This situation
is avoided by:
( 1 ) Taking only pure O 2 in breathing cylinders
( 2 ) Replacing some N 2 by He, which is more
soluble than N 2.
( 3 ) Replacing some N 2 by He, which is less soluble
than N 2.
( 4 ) This situation can not be avoided and therefore
pain killers are consumed
43. x % (w/v) aqueous solution of HCHO and y % (w/v)
aqueous solution of glucose are isotonic with each
other. The ratio x : y will be:
44. The abnormal molecular mass of CH 3 COOH when
dissolved in benzene is found to be 80 g/mol. The
percentage of CH 3 COOH present in dimeric form in
solution is:
45. A solution containing 4g of polyvinyl chloride in 1
litre of dioxane was found to have an osmotic
pressure of 6 × 10
- 4 atm at 300 K. The molecular
mass of polymer is:
(1) 3 × 10
3 (2) 1.6 × 10
5
(3) 5 × 10
4 (4) 6.4 × 10
2
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