Biphenyl, C12H10, is a nonvolatile, nonionizing solute that is soluble in benzene, C6H6. At 25 °C, the vapor pressure of pure benzene is 100.84 torr. What is the vapor pressure of a solution made from dissolving 11.1 g of biphenyl in 29.1 g of benzene?

Answer 1

mols biphenyl = grams/molar mass.
mols benzene = grams/molar mass.
Xbenzene = mols benzene/total mols

Psoln = Xbenzene*P^obenzene