Question

The mole fractions in the liquid phase of an ideal liquid solution in equilibrium with its vapour generally differ from those in the vapour phase. Raoult's law expresses the partial pressure of a component i in the vapour in equilibrium with an ideal liquid solution at temperature T.

The vapour pressure of benzene is 74.7 mmHg at 293K , and that of toluene is 22.3 mmHg at 293K . A random solution of benzene and toluene at 293K has a vapour pressure of 46.0 mmHg.

a) Determine the benzene mole fraction in the liquid phase of the solution.

b) Determine the benzene mole fraction in the vapour phase of the solution.