Dear Student,
Raoult’s law states that in a solution, the vapour pressure of a component at a given temperature is equal to the mole fraction of that component in the solution multiplied by the vapour pressure of that component in the pure state.
For a volatile solute,
Let the vapour pressure of pure solvent be
then the vapour pressure of solution containing volatile solute is given by :
where is the mole fraction of solvent.
Regards.