The same amount of electric current is apassed through aqueous solution of MgSO₄ and AlCl₃. If 2.8 g Mg metal is deposited at amount of Al metal deposited in second cell will be

1. 2.1 g

2. 2.49 g

3. 3.15 g

4. 3.73g

If partial pressure of oxygen is 0.5 atm and K_H = 1.4 × 10^-3 M/atm, then the amount of oxygen dissolved in 100 ml water at 298K is-

Which of the following pairs exhibit positive deviation from Raoult's law?
 

(i) Chloroform and Acetone

(ii) Carbon disulphide and Acetone

(iii) Ethanol and Acetone

(iv) Phenol and Aniline

1. i and ii

2. ii and iii

3. i and iv

4. ii and iv

The relative lowering of vapour caused by dissolving 71.3 g of a substance in 1000 g of water is 7.13 x 10^-3. The molecular mass of the substance is-

1. 180 g mol^-1

2. 18 g mol^-1

3. 1.8 g mol^-1

4. 360 g mol^-1

If molality of the dilute solution is doubled, the value of molal depression constant (K_f) will be?

(1) doubled

(2) halved

(3) tripled

(4) unchanged

The van't Hoff factor [i] for a dilute aqueous solution of the strong electrolyte barium hydroxide is?

(1) 0

(2) 1

(3) 2

(4) 3

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

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

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

The molar heat of vapourization of toluene is AHv. If its vapour pressure at 315 K is 60 torr & that at 356K is300 torr then AHv = ? (log 2 = 0.3)

(1) 37.5 kJ/mole

(2) 3.75 kJ/mole

(3) 37.5 J/mol

(4) 3.75 J/mole