At 100°C the vapour pressure of a solution of 6.5 g of a solute in 100 g water is 732 mm. If K_b = 0.52, the boiling point of this solution will be

(1) 100°C

(2) 102°C

(3) 103°C

(4) 101°C

Which of the following statements about the composition of the vapour over an ideal 1:1

molar mixture of benzene and toluene is correct? Assume that the temperature is

constant at 25°C.

(Given, vapour pressure data at 25°C, benzene = 12.8 kPa, toluene = 3.85 kPa)

1. The vapour will contain a higher percentage of toluene

2. The vapour will contain equal amounts of benzene and toluene

3. Not enough information is given to make a prediction

4. The vapour will contain a higher percentage of benzene

Which one is not equal to zero for an ideal solution?

1. ΔH_mix 

2. ΔS_mix

3. ΔV_mix

4. ΔP=P_Observed-P_Raoult

Which one of the following elctrolytes has the same value of van't Hoff's factor(i) as

that of Al₂(SO₄)₃  (if all are 100% ionised)? 

1. K₂SO₄

2. K₃[Fe(CN)₆]

3. Al(NO₃)₃

4. K₄[Fe(CN)₆]

Of the following 0.10 m  aqueous solutions, which one will exhibit the largest freezing

point depression?

1. KCl

2. C₆H₁₂O₆

3. Al₂(SO₄)₃

4. K₂SO₄

p_A and p_B are the vapour pressure of pure liquid components, A and B, respectively of an

ideal binary solution.If x, represents the mole fraction of component A, the total pressure

of the solution will be.

1. p_A + x_A(p_B-p_A)

2. p_A + x_A(p_A-p_B)

3. p_B + x_A(p_B-p_A)

4. p_B + x_A(p_A-p_B)

The freezing point depression constant format is -1.86°C m^-1. If 5.00g Na₂SO₄ dissolved

in 45.0 g H₂O, the freezing point is changed by -3.82°C. Calculate the van't Hoff factor

for NaSO4

1. 2.63

2. 3.11

3. 0.381

4. 2.05

The van't Hoff factor, i for a compound which undergoes dissociation in one solvent and

association in other solvent is respectively.

1. less than one and less than one

2. greater than one and less than one

3. greater than one and greater than one

4. less than one and greater than one

An aqueous solution is 1.00 molal in KI. Which change will cause the vapour pressure of

the solution to increase ?

1. Addition of NaCl

2. Addition of Na₂SO₄

3. Addition of 1.00 molal KI

4. Addition of water

A solution of sucrose (molar mass = 342 g mol^-1) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water.

The freezing point of the solution obtained will be:

 (K_f for water = 1.86 K kg mol^-1)

1. -0.372 $°$C

2. 0.372 $°$C

3. 0.572 $°$C

4. -0.572 $°$C