'x' grams of benzene and 'y' grams of toluene, it is said that the vapor pressure of benzene is 75 mmHg and that of toluene is 22 mmHg. Find mole fraction in the vapor state,
What I do not understand is how different states can have different values for mole fraction? Do the moles change with a change of state?
More precisely how does the fraction of mole in each state look at transition states? As in say I started with 100 moles in the liquid phase, when it reaches the point where it is about to turn to gas (b.p) how much fraction of moles are gas and how much are liquid?