Elements P and Q form two types of non-volatile, non-ionizable compounds PQ and PQ_2. When 1 g of PQ is dissolved in 50 g of solvent 'A', Δ T_b was…

Elements P and Q form two types of non-volatile, non-ionizable compounds PQ and $\displaystyle \mathrm{PQ}_2$. When $\displaystyle 1$ g of PQ is dissolved in $\displaystyle 50$ g of solvent 'A', $\displaystyle \Delta \mathrm{T}_{\mathrm{b}}$ was $\displaystyle 1.176$ K while when $\displaystyle 1$ g of $\displaystyle \mathrm{PQ}_2$ is dissolved in $\displaystyle 50$ g of solvent ' A ', $\displaystyle \Delta \mathrm{T}_{\mathrm{b}}$ was $\displaystyle 0.689$ K . ( $\displaystyle \mathrm{K}_{\mathrm{b}}$ of ' A ' $\displaystyle =5 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$ ). The molar masses of elements P and Q (in $\displaystyle \mathrm{g} \mathrm{mol}^{-1}$ ) respectively, are :