A substance ' $X$ ' ( 1.5 g ) dissolved in 150 g of a solvent ' $Y$ ' (molar mass $=300 \mathrm{~g}

Question

A substance ' $X$ ' ( 1.5 g ) dissolved in 150 g of a solvent ' $Y$ ' (molar mass $=300 \mathrm{~g} \mathrm{~mol}^{-1}$ ) led to an elevation of the boiling point by 0.5 K . The relative lowering in the vapour pressure of the solvent' $\mathrm{Y}^{\prime}$ is $\_\_\_\_$ $	imes 10^{-2}$. (nearest integer) 
[Given : $\mathrm{K}_{\mathrm{b}}$ of the solvent $=5.0 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$ ] 
Assume the solution to be dilute and no association or dissociation of $X$ takes place in solution.

Professor PC Thomas Classes · Answer

See detailed solution for explanation.