When the mixture of two immiscible liquids (water and nitrobenzene) boils at `372` K and the vapour pressure at this temperature are `97.7"k Pa"("H"_(2)"O") " and 3.6 k Pa"("C"_(6)"H"_(5)"NO"_(2)).` Calculate the weight `%` of nitrobenzene in the vapour.

Answer

0.2011

Explanation

Let vapour contains `"W"_(1)" gm of" " C"_(6)"H"_(5)"NO"_(2) and "W"_(2)" gm of"" H"_(2)O"`
`"n"_(1)="w"_(1)/123," n"_(1)="w"_(1)/18`
For gases
Ratio of moles `=` Ratio of pressure
`"n"_(1):"n"_(2)=3.6:97.7`
`"w"_(1)/123xx18/"w"_(2)=3.6/97.7`
`"w"_(1)/"w"_(2)=(3.6xx123)/(18xx97.7)=0.252`
`"w"_(1)="w"("let"),"w"_(1)=0.252"w"`
`%"w"_(1)=(0.252"w")/(1.252"w")xx100`
`=20.11%`