Question

Calculate the vapor pressure (in torr) of a 35°C solution of ethanol and propanol where the mole fraction of propanol is .75. Assume Ideal behavior P°ethanol35=100torr P°propanol35=36torr

Answer 1

The vapor pressure (in torr) of a 35°C solution : 52 torr

Further explanation

Given

x propanol = 0.75

P°ethanol=100 torr

P°propanol=36 torr

Required

the vapor pressure

Solution

Raoult's Law

P solution = xA.P°A +xB.P°B

x ethanol = 1- 0.75 = 0.25

Input the value :

P solution = 0.25 x 100 + 0.75 x 36

P solution = 25 + 27

P solution = 52 torr