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)

Calculate the van’t Hoff factor (i) for Na₂SO₄ when 5.00 g of Na₂SO₄ is dissolved in 45.0 g of water and the freezing point decreases by 3.82°C.

Given: Kf for water = 1.86°C kg mol⁻¹.

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

Calculate the number of moles of ions produced when 1 mole of Co(NH₃)₅(NO₂)Cl dissolves completely in water,
if a 0.0020 m aqueous solution freezes at −0.00732°C.

(Given:Kf = 1.86°C/m)

0.5 molal aqueous solution of a weak acid (HX) is 20% ionised. If K_f for water is 1.86 K kg mol^-1, the lowering in freezing point of the solution is:

(1) -1.12 K

(2) 0.56 K

(3) 1.12 K

(4) - 0.56 K

1.00 g of a non-electrolyte solute (molar mass 250g/mol) was dissolved in 51.2 g of benzene. If the freezing point depression constant, K_f of benzene is 5.12 K kg mol^-1, the freezing point of benzene will be lowered by:-

(1) 0.4 K

(2) 0.3 K

(3) 0.5 K

(4) 0.2 K