200 mL of an aqueous solution contains 1.26 g of protein. The osmotic pressure of this solution at 300 K is found to be 2.57 × 10^–3 bar. The molar mass of protein will be:

(Use: R = 0.083 L bar mol^–1 K^–1)

1.	61038 g mol–1	2.	51022 g mol–1
3.	122044 g mol–1	4.	31011 g mol–1

A 0.1 molal aqueous solution of a weak acid (HA) is 30 % ionized. If K_f for water is 1.86 °C/m, the freezing point of the solution will be:

Isotonic solutions have the same:

1. Vapour pressure

2. Freezing temperature

3. Osmotic pressure

4. Boiling temperature

If 8 g of a non-electrolyte solute is dissolved in 114 g of n-octane to reduce its vapor pressure to 80 %, the molar mass (in g mol^–1) of the solute is:

[Molar mass of n-octane is 114 g mol^–1]

The positive deviations from Raoult’s law mean the vapour pressure is:

1. Higher than expected.
2. Lower than expected.
3. As expected.
4. None of the above

The type of inter-molecular interactions present in:

Henry’s law constant for the solution of methane in benzene at 298 K is 4.27 × 10⁵ mm Hg. The mole fraction of methane in benzene at 298 K under 760 mm Hg will be:

1. 1.85 × 10^–5

2. 192 × 10^–4

3. 178 × 10^–5

4. 18.7 × 10^–5

The solubility of gases in liquids generally decreases as temperature increases.
The primary reason for this behavior is:

Which law is applied when deep-sea divers use a breathing mixture of oxygen and less soluble helium to minimise the painful effects caused by the increased dissolution of gases in blood at high pressure?