List of top Physical Chemistry Questions on Phase equilibria asked in IIT JAM CY

The total vapour pressure of an ideal binary liquid mixture of benzene and toluene is 0.3 bar. The vapour pressure of pure benzene is 0.5 bar and that of toluene is 0.2 bar. The mole fraction of benzene in this mixture is _______.
(rounded off to two decimal places)

The vapor pressure of a dilute solution of a non-volatile solute and the vapor pressure of the pure solvent at the same temperature are P and P*, respectively. \(\frac{P^*-P}{P^*}\) is equal to 
(Assume that the vapor phase behaves as an ideal gas)

The phase diagram of water is best represented by

At constant temperature, 6.40 g of a substance dissolved in 78 g of benzene decreases the vapor pressure of benzene from 0.125 atm to 0.119 atm. The molar mass of the substance is ____g mol^-1. (round off to one decimal place)
[Given: Mol. wt. of benzene = 78 g mol^-1]