CHEMISTRY Topic : LIQUID SOLUTION TUTORIAL SHEET-1

1. Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is
(a) 3.28 mol kg-1 (b) 2.28 mol kg-1 (c) 0.44 mol kg-1 (d) 1.14 mol kg-1

2. Which one of the following statements is false?

(a) Raoult’s law states that the vapour pressure of a component over a solution proportional to its mole
fraction.
(b) The osmotic pressure (  ) of a solution is given by the equation  =MRT, where, M is the molaity
of the solution
(c) The correct order of osmotic pressure for 0.01 m aqueous solution of each compound is
BaCl2  KCl  CH3COOH  sucrose
(d) Two sucrose solutions of same molarity prepared in different solvents will have the same freezing
point depression.

3. In a 0.2 molar aqueous solution of a week acid HX, the degree of ionization is 0.3. Taking Kf for water
as 1.85, the freezing point of the solution will be nearest to
(a) – 0.480 C (b) – 0.360 C (c) – 0.260 C (d) + 0.480

4. The vapour pressure of benzene at a certain temperature is 640 mm of Hg. A non-volatile and non-
electrolyte solid weighing 2.175 g is added to 39.08 g of benzene. The vapour pressure of the solution
is 600 mm of Hg. What is the molecular weight of solid substance?
(a) 69.60 (b) 49.59 (c) 59.60 (d) 108.30

5. Which of the following salt has the same value of van’t Hoff factor as that of K3[Fe(CN)6]?
(a) Na2SO4 (b) Al(NO3)3 (c) Al2(SO4)3 (d) Fe3O4

6. The molecular weight of NaCl, determined by studying freezing point depression of its 0.5% aqueous
solution is 30. The apparent degree of dissociation of NaCl is?
(a) 0.95 (b) 0.50 (c) 0.60 (d) 0.30

7. Assume that incremental amounts of a volatile solute are added to a solvent so that the mole fraction of
solute are added to a solvent so that the mole fraction of solute varies from 0 to 1. A plot of the partial
pressure of the solute vs. mole fraction of solute will
(a) be linear with slope equal to the vapour pressure of the pure solute.
(b) be linear with slope equal to the vapour pressure of the pure solvent.
(c) be linear with slope equal to the sum of the vapour pressures of pure solvent and pure solute.
(d) vary exponentially with the fraction of the solute.

8. A 1.96% solution of H2SO4 in water freezes at – 0.794oC. If Kf of water is 1.86 K kg/mol and density
of solution is 1.0 g/mL, the value of ionization constant for the following reaction is
HSO −4 H + + SO 24−
(a) 0.146 (b) 3.3 10−3 (c) 2 10−4 (d) 5 10− 6

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9. Relative decrease in vapour pressure of an aqueous solution containing 2 moles [Cu(NH3 )3 Cl]Cl in 3
moles H2O is 0.50. On reaction with AgNO3, this solution form
(a) 1 mole AgCl (b) 0.25 mole AgCl (c) 2 mole AgCl (d) 0.40 mole AgCl

10. Consider equimolal aqueous solution of NaHSO4 and NaCl with Tb and Tb' as their respective boiling
Tb'
point elevations. The value of Lt , will be
M → 0 T
b

2
(a) 1 (b) 1.5 (c) 3.5 (d)
3

11. An aqueous solution containing 7.45 gm of KCl in 180 gm of water at 100oC and V.P. of solution is
656.36 torr. Calculate degree of dissociation of KCl.
(a) 0.75 (b) 0.2 (c) 0.5 (d) 0.7

12. 100 mL of 0.2 M MgCl2 is mixed with 100 mL of 0.1 N NaCl at 100oC. V.P. of resulting solution will
be : (assuming molarity = molality)
(a) 750 torr (b) 753 torr (c) 754.5 torr (d) 756.6 torr

13. In 100 mL of 0.1 M NaCl, 200 mL of 0.1 M MgCl2 is added at 100oC. Calculate B.P. of resulting
solution.
[Kb (H2O) = 0.512 K Kg mol-1].
(a) 100.12oC (b) 100.36oC (c) 100.136oC (d) None of these

14. For water, variation of V.P. with temperature is given as :

For a solution of glucose having mole fraction of glucose 0.2, lowering in V.P. at 120oC will be :
(a) 1620 torr (b) 0.2 torr (c) 162 torr (d) 152 torr

15. 0.1 M aqueous solution of K4[Fe(CN)6] at 27oC, have osmotic pressure 90 R. Percentage dissociation
of K4[Fe(CN)6] is :
(a) 75% (b) 25% (c) 50% (d) 30%

16. 100 mL of an aqueous solution containing 0.1 M NaCl solution. In Kb (H2O) = 0.52oC kg mol-1, normal
B,P. of solution is :
(a) 100.052oC (b) 100.104oC (c) 100.12oC (d) 100.16oC

17. 1 mole of liquid A and 1 mole liquid B are mixed together at 90oC. If PAo = 100 torr, PBo = 200 torr, then
V.P. of 1st distillate will be :
500
(a) 150 torr (b) 130 torr (c) torr (d) none of these
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18. Graph between ln (P) and (K ) for diethyl either and CCl4 is given as :
T
(where P = V.P. of liquid)

Then select the correct option.

(a) Hvap(C2H5OC2H5) > Hvap (CCl4) (b) V.P. of (CCl4) < V.P. (C2H5OC2H5)
(c) Hvap(C2H5OC2H5) < Hvap(CCl4) (d) None of the above

19. For 0.1 M, aqeous solution of CH3COOH (van’t Hoff factor = 1.01), calculate valueof Ka for acid.
(a) 10-3 (b) 10-7 (c) 10-5 (d) None of these

20. 0.005 M K4[Fe(CN)6] is isotonic with 0.01 M glucose. Degree of dissociation of K4[Fe(CN)6] is :
(a) 75% (b) 50% (c) 25% (d) 100%

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 ANSWER-KEY

CHEMISTRY

Topic : Liquid Solution

Tutorial Sheet-1

11. 1.12. (b)

13. 2.14. (d)
15. 3.16. (a)
17. 4.18. (a)
19. 5.20. (b)
21. 6.22. (a)
23. 7.24. (a)
25. 8.26. (b)
27. 9.28. (a)
29. 10.
30. (d)
31. 11.
32. (c)
33. 12.
34. (c)
35. 13.
36. (c)
37. 14.
38. (b)
39. 15.
40. (c)
41. 16.
42. (b)
43. 17.
44. (c)
45. 18.
46. (a)
47. 19.
48. (c)
49. 20.
50. (c)

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