The partial pressure ratio `P_(A)^(@):P_(B)^(@)` for the two volatile liquid A and B and `P_(A)^(@): P_(B)^(@)=1:2` and mole ratio is `X_(A): X_(B)=1:2`. What is the mole fraction of A ?

Options

A. `0.33`
B. `0.25`
C. `0.20`
D. `0.52`

Answer

C

Explanation

`p_(A)=x.p , p_(B)=x.p`
`p_(A)=x_(p),p_(B)=2x.2p`
Total pressure `p =p_(A)+p_(B)`
`p=xp+4xp=5xp`
`therefore` Mole fraction of,
`A(X_(A))=(p_(A))/(p)=(xp)/(5xp)=(1)/(5)=0.2`