The azeotropic mixture of water and ethanol boils at 78.15 ^oC. When this mixture is distilled, it is possible to obtain-

1. Pure H₂O

2. Pure C₂H₅OH

3. Pure H₂O as well as pure C₂HOH

4. Neither H₂O nor C₂H₅OH in their pure state 

The freezing point of depression constant (K_f ) of benzene is 5.12 K kg mol^–1. The freezing point depression for the solution of molality 0.078 m containing a non-electrolyte solute in benzene is:
(rounded off up to two decimal places)
1. 0.80 K
2. 0.40 K
3. 0.60 K
4. 0.20 K

On dissolving sugar in water at room temperature solution feels cool to touch. Dissolution of sugar will be most rapid under the following case is:

1.  Sugar crystals in cold water
2.  Sugar crystals in hot water
3.  Powdered sugar in cold water
4.  Powdered sugar in hot water

Colligative properties are dependent on which of the following factors?

A solution that has the highest boiling point among the following is:

1. 1.0 M NaOH

2. 1.0 M Na₂SO₄ 

3. 1.0 M NH₄NO₃

4. 1.0 M KNO₃

The value of Henry's law constant:

40% (w/V) of NaCl solution (density = 1.14 g/ml) is equivalent to: 
1. $0.35\times {10}^5 ppm$
2. $4\times {10}^6 ppm$
3. $3.5\times {10}^6 ppm$
4. $0.35\times {10}^6 ppm$

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]

Isotonic solutions have the same:

1. Vapour pressure

2. Freezing temperature

3. Osmotic pressure

4. Boiling temperature

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: