Tim, Shawn, Mike -- you're not fooling us by switching names.
If you post what part of the problem confuses you, someone may be able to help you.
What is the total vapor pressure4 at 20° C of a liquid solution containing 0.30 mole fraction benzene, C6H6, and 0.70 mole fraction toluene, C6H5CH3? Assume that Raoult’s law holds for each component of the solution. The vapor pressure of pure benzene at 20° C is 75 mmHg; that of toluene at 20° C is 22 mmHg. Express your answer in mmHg.
2 answers
Pbenzene = mole fraction benzene*normal vapor pressure benzene.
Ptoluene = mole fraction toluene*normal vapor pressure toluene.
Total pressure = sum of each partial pressure.
Ptoluene = mole fraction toluene*normal vapor pressure toluene.
Total pressure = sum of each partial pressure.