Question

What is the mole ratio of benzene `(P_(B)^(@)=150 t o r r)` and toluence `(P_(tau)^(@)=50 t o rr)` in vapour phase if the given solution has a vapour phase if the given solution has a vapour pressure of `120` torr ?
A. `7:1`
B. `7:3`
C. `8:1`
D. `7:8`

Answer 1

Correct Answer - 1
`P=P_(B)^(@)X_(B)+P_(T)^(@)X_(T)`
`120=150(X_(B))+50(1-X_(B))`
`100" "X_(B)+70`
`X_(B)=0.7`
`Y_(B)=(X_(B)p_(B)^(@))/(P)=(0.7xx150)/(120)=0.075" "(Y_(B))/(Y_(T))=(7)/(1)" "Y_(T)=1-0.875=0.125`