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)

Limiting molar conductivity of NH₄OH (i.e Åm(NH₄OH)) is equal to:-

1. Å_m (NH₄Cl)+Å_m(NaCl)-Å_m(NaOH) 

2. Å_m(NaOH)+Å_m(NaCl)-Å_m(NH₄Cl)

3. Å_m(NH₄OH)+Å_m(NH₄Cl)-Å_m(HCl)

4. Å(NH₄Cl)+Å(NaOH)-Å(NaCl)

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

An increase in equivalent conductance of a strong electrolyte with dilution is mainly due

to

1. increase in ionic mobility of ions

2. 100% ionisation of electrolyte at normal dilution

3. increase in both, i.e. number of ions and ionic mobility of ions

4. increase in number of ions

The equivalent conductance of M/32 solution of a weak monobasic acid is 8.0 mho cm² and at infinite

dilution is 400 mho cm² .The dissociation constant of this acid is.

1. 1.25x10^-5

2. 1.25x10^-6

3. 6.25x10^-4

4. 1.25x10^-4

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)

Kohlrausch's law states that at

(1) finite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte.

(2) infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte depending on the nature of the other ion of th electrolyte.

(3) infinite dilution, each ion makes definite contribution to conductance of an electrolyte whatever be the nature of the other ion of the electrolyte.

(4) infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte.