Consider the following liquid-vapor equilibrium 
Liquid  ↔  Vapour 
Which of the following relation is correct?

1. \(\frac{dlnp}{dT}=\frac{-\Delta H_v}{RT}\)

2. \(\frac{dlnp}{dT^2}=\frac{-\Delta H_v}{T^2}\)

3. \(\frac{dlnp}{dT}=\frac{\Delta H_v}{RT^2}\)

4. \(\frac{dlnG}{dT^2}=\frac{-\Delta H_v}{RT^2}\)

The boiling point of 0.2 mol kg^–1 solution of X in water is greater than the equimolal solution of Y in water. The correct statement in this case is:

The electrolyte having the same value of Van't Hoff factor (i) as that of Al₂(SO₄)₃  (if all are 100% ionized) is:

1. K₂SO₄
2. K₃[Fe(CN)₆]
3. Al(NO₃)₃
4. K₄[Fe(CN)₆]

p_A and p_B are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution.
If X_A 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 for water is 1.86 ^oC m^-1. If 5.00 g Na₂SO₄ is dissolved in 45.0 g H₂O, the freezing point is changed by -3.82 ^oC. The Van’t Hoff factor for Na₂SO₄ is:

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 ^oC
2. –0.520 ^oC
3. +0.372 ^oC
4. –0.570 ^oC

A 0.0020 m aqueous solution of an ionic compound Co(NH₃)₅(NO₂)Cl freezes at -0.0073 ^oC. The number of moles of ions that 1 mol of ionic compound produces on being dissolved in water will be:
(K_f = -1.86 ^oC/m)

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

1. -1.12 K

2. 0.56 K

3. 1.12 K

4. -0.56 K

A solution containing 10 g/dm³ of urea (molecular mass = 60 g mol^-1) is isotonic with a 5 % solution of a non-volatile solute. The molecular mass of this non-volatile solute is: