1Propanol (1=20.9 Torr at 25 C) and 2propanol (2=45.2 Torr at 25 C) form ideal solutions in all proportions. Let 1 and 2 represent the mole fractions of 1propanol and 2propanol in a liquid mixture, respectively, and 1 and 2 represent the mole fractions of each in the vapor phase. For a solution of these liquids with 1=0.520, calculate the composition of the vapor phase at 25 C.