19.5 g of CH₂FCOOH is dissolved in 500 g of water. The van’t Hoff factor and dissociation constant of fluoroacetic acid will be respectively -

($∆{\mathrm{T}}_{\mathrm{f}}$ = 1.00 K )

1) 20.75 , 4.77 x 10^-3

2) 1.075 ,  4.77 x 10^-2

3) 2.073 , 3.07 x 10^-4

4) 1.075 , 3.07 x 10^-3

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

100 g of liquid A (molar mass 140 g mol^–1) was dissolved in 1000 g of liquid B (molar mass 180 g mol^–1). The vapour pressure of pure liquid B was found to be 500 torr. If the total vapour pressure of the solution is 475 torr, the vapour pressure of pure liquid A will be -

1. 326 torr

2. 226 torr 

3. 360.7 torr

4. 280.7 torr

The major component of air is nitrogen with approximately 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K. if the Henry’s law constant for nitrogen at 298 K is 6.51 × 10⁷ mm respectively, then the composition of nitrogen in air will be :

1. 12.4 x 10⁻⁵

2. 9.22×10⁻⁵

3. 3.54 x 10⁻⁵

4. 4.96 x 10⁻⁵

The amount of CaCl₂ (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27 °C is-

1. 1.02 g

2. 4.35 g

3. 2.87 g

4. 3.42 g

The type of inter molecular interactions present in

The solubility of a gas in a liquid decreases with an increase in temperature because:

To minimise the painful effects accompanying deep sea diving, oxygen diluted with less soluble helium gas is used as breathing gas by the divers. This is an example of the application of - 

The example of gas in a solid type solution is:

1. Solution of hydrogen in palladium.

2. Ethanol dissolved in water.

3. Camphor vapours in N₂ gas.

4. Amalgams.