Total vapour pressure of a mixture of 1 mol A (p_A°  = 150 torr) and 2 mol B (${\mathrm{p}}_{\mathrm{B}}^{°}$ = 240 torr) is 200 torr. In this case:-

1. There is a positive deviation from Raoult's law
2. There is a negative deviation from Raoult's law
3. There is no deviation from Raoult's law
4. None of these 

The vapour pressure of a pure liquid solvent A is 0.80 atm. When a non-volatile substance B is added to the solvent, its vapour pressure drops to 0.60 atm.
Mole fraction of the component B in the solution is:

The Vapour pressure of CCl₄ at 25°C is 143 mm Hg. 0.5 g of a non-volatile solute (mol. wt. 65) is dissolved in 100 ml of CCl₄. The vapor pressure of the solution is-

(Density of CCl₄ = 1 .58 g/cm³$)$ 

1. 141.93 mm Hg

2. 94.39 mm Hg

3. 199.34 mm Hg

4. 143.99 mm Hg

The equal weight of a solute is dissolved in an equal weight of two solvents A and B to form a very dilute solution. The relative lowering of vapour pressure for solution B has twice the relative lowering of vapour pressure for solution A.

If ${\mathrm{M}}_{\mathrm{A}}$ and ${\mathrm{M}}_{\mathrm{B}}$ are the molecular weights of solvents A and B respectively, then:

1. ${\mathrm{M}}_{\mathrm{A}}$ = ${\mathrm{M}}_{\mathrm{B}}$

2. ${\mathrm{M}}_{\mathrm{B}}$ = 2${\mathrm{M}}_{\mathrm{A}}$

3. ${\mathrm{M}}_{\mathrm{A}}$ = 4${\mathrm{M}}_{\mathrm{B}}$

4. ${\mathrm{M}}_{\mathrm{A}}$ = 2${\mathrm{M}}_{\mathrm{B}}$

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]

One mole of sugar is dissolved in three moles of water at 298 K. The relative lowering of vapour pressure is:

The largest freezing point depression among the following 0.10 m solutions is shown by:

The incorrect statement among the following is:

The vapour pressure of water in the solution having 50 g of urea dissolved in 850 g of water is:

(Vapor pressure of pure water at 298 K is 23.8 mm Hg) 

1. 23.40 mm of Hg

2. 33.46 mm of Hg

3. 12.76 mm of Hg

4. 87.12 mm of Hg