Two volatile substances, A and B are dissolved in one another and the resulting solution has a vapor pressure of 137 torr. If the mole fraction of B is 0.230 and the vapor pressure of pure B is 162 torr, what is the vapor pressure of pure A in torr?

Vapor pressure of pure A is 129.5torr

Explanation:

When two or more liquids produce an ideal solution, the vapour pressure of the mixture follows the equation (Raoult's law):

Where P is vapour pressure and X mole fraction of liquids A and B. Pt is the pressure of the solution

As mole fraction of B is 0.230, mole fraction of A is:

Computing in Raoult's law with the given values:

the answers are

c and c