When 20 g of naphthoic acid (C₁₁H₈O₂) is dissolved in 50 g of benzene, a freezing point depression of 2 K is observed. What is the Van’t Hoff factor (i)?
(K_f = 1.72 K kg mol^–1)

1.	0.5	2.	1
3.	2	4.	3

An aqueous solution of non-electrolyte 'A' with molecular mass 60 contains 6 g in 500 mL and has a density equal to 1.05 g $m{L}^{-1}$.  The molality of solution  is

(1) 1.25

(2) 0.19

(3) 0.25

(4) 0.30

At a given temperature, total vapour pressure (in Torr) of a mixture of volatile components A and B is given P = 120 - 75 $x_B$.  Hence vapour pressure of pure A and B respectively (in Torr) are

(1) 120, 75

(2) 120, 195

(3) 120, 45

(4) 75, 45

$K_4\left[Fe{\left(CN\right)}_6\right]$ is 50% dissociated then the value of Van't Hoff factor (i)

(1) 2

(2) 2.2

(3) 2.5

(4) 3

When mercuric iodide is added to the aqueous solution of potassium iodide is 

(1) Freezing point is raised

(2) Freezing point is lowered

(3) Freezing point does not change

(4) Boiling point does not change

Aluminium phosphate is 100% ionized in 0.01 m aqueous solution.  Hence, $∆T_b/k_b$ is

(1) 0.01

(2) 0.015

(3) 0.0175

(4) 0.02

Van't Hoff factor for $SrC{l}_2$ at 0.01 M is 1.8.  Percentage dissociation of $SrC{l}_2$ will be

(1) 70

(2) 55

(3) 40

(4) 30

Aqueous solutions of 0.004 M Na₂SO₄ and  0.01 M Glucose are isotonic. The degree of dissociation of Na₂SO₄ is-

1. 25% 

2. 60%

3. 75% 

4. 85%

At 28oC, the vapour pressure of pure liquid A (mol.wt = 40) is 100 torr, while that of pure liquid B is 40 torr, (mol. wt = 80). The vapour pressure at 25^oC of a solution containing 20 g of each A and B is:

1. 80 torr

2. 59.8 torr

3. 68 torr

4. 48 torr

The vapour pressure of an aqueous solution of sucrose at 373 K is found to be 750 mm Hg.
The molality of the solution at the same temperature will be: