Raoult's Law and Mole Fraction

Raoult's Law states that the partial vapor pressure of each component of an ideal mixture of liquids is equal to the vapor pressure of the pure component multiplied by its mole fraction in the mixture.


As we know that the liquid and vapour in a container are at dynamic equilibrium,


So the mole fraction which is mentioned in Raoult's Law is measured at equilibrium or initially?




Raoults Law says that, for an ideal liquid mixture, the partial pressure of each component **in the gas phase** is equal to the vapor pressure of the pure component (at the temperature of the system) times the mole fraction of that component in the liquid phase. If the system is at equilibrium, the mole fraction to use in the equation is the **current** mole fraction.


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