Question

Two liquids a and b from ideal solution,at 333k ,the vapour pressure of a solution containing a and b in 1:2 molar ratiois 300 torr and of a slotion containing equal number of moles of a and b is 350torr.What are the vapour pressure of pure a and b at 333k?

Answer 1

Since P=xAP0A+xBP0B

⇒(11+3)P0A+(31+3)P∘B=550mm Hg

⇒(11+4)P0A+(41+4)P∘B=560mm Hg

That is,

0.25P0A+0.75P0B=550mm Hg

0.20P0A+0.8P0B=560mm Hg

Solving for P0A and P0B we get,

P0A=400 mm Hg

P0B=600 mm Hg