A solution containing 60 g of a non-volatile solute in 250 g of water freezes at 270.67 K. Calculate the molar mass of the solute. ( K_f of water =…

\[\begin{aligned} & \Delta \mathrm{T}_{\mathrm{f}}=\mathrm{K}_{\mathrm{f}} \mathrm{~m} \\ & \mathrm{M}_{\mathrm{B}}=\frac{\mathrm{K}_{\mathrm{f}} \times \mathrm{W}_{\mathrm{B}} \times 1000}{\mathrm{~W}_{\mathrm{A}} \times \Delta \mathrm{T}_{\mathrm{f}}} \\ & =273 \cdot 15-270 \cdot 67=2 \cdot 48 \mathrm{~K} \\ & \mathrm{M}_{\mathrm{B}}=\frac{1 \cdot 86 \times 60 \times 1000}{250 \times 2 \cdot 48} \\ & =180 \mathrm{~g} \mathrm{~mol}^{-1} \end{aligned} \]