Raoult gave the quantitative relationship between the solutions, then the relationship is known as raoult's law which states that for a solution of volatile liquids, the partial pressure vapour pressure of each component in the solution is directly proportional to its mole fraction.
Thus, for components 1.
P1 ∝ x1
and P1 = P10 x1
Where P10 is the vapour pressure of pure component 1 at the same temperature.
Simply, for componant 2
P2 = P20 x2
where P20 represents the vapour pressure of the pure component.
Raoult's law in general form can be stated as, for any solution the partial vapour pressure of each volatile component in the solution is directly proportional to its mole fraction.