Question
Show that the relative lowering of vapour pressure of a solution containing a nonvolatile solute is equal to the mole fraction of the solute in the solution?
Solution
Answer:
Raoult established that the lowering of vapour pressure depends only on the concentration of the solute particles and it is independent of their identity.
establishes a relation between vapour pressure ofthe solution, mole fraction and vapour pressure of the solvent, i.e.
Lowering of vapour pressure
=
Lower of vapour pressure
or