Water and chlorobenzene are immiscible liquids. Their mixture boils at `89^(@)C` under reduced pressure of `7.7 xx10^(4) pa`. The vapour pressure of pure water at `89^(@)C` is `7 xx10^(4) pa` Mass per cent of chlorobenzene in the distillate is :

Options

A. 50
B. 60
C. `78.3`
D. `38.46`

Answer

4

Explanation

`(W_(A))/(W_(B))=(P_(A)^(@))/(P_(B)^(@))xx(M_(A))/(M_(B))rArr(0.7)/(7)xx(112.5)/(18)rArr0.625`
`%(W_(A))/(W_(A)+W_(B))xx100=(0.625)/(1.625)xx100rArr38.46`