Chemistry - Liquid Solution Question with Solution | TestHub

Elevation in boiling point is given by $\Delta T_b=T_b-T_b^0$

$\Delta T_b=319.4-319=0.4$ K

Using the formula for elevation in boiling point:

$\Delta T_b=K_b\times m=K_b\times \frac{w_2\times 1000}{M_2\times w_1}$

Substituting the given values:

$0.4=2.4\times \frac{4\times 1000}{M_2\times 100}$

$0.4=\frac{96}{M_2}$

$M_2=\frac{96}{0.4}=240$ g mol${}^{-1}$

Answer: $240{\text{gmol}}^{-1}$