0.3 g of acetic acid ( M =60 g mol^-1) dissolved in 30 g of benzene shows a depression in freezing point equal to 0.45^° C. Calculate the percentage…

\[\begin{aligned} & \Delta \mathrm{T}_{\mathrm{f}}=\mathrm{i} \mathrm{~K}_{\mathrm{f}} \frac{\mathrm{~W}_{\mathrm{B}}}{\mathrm{M}_{\mathrm{B}}} \times \frac{1000}{\mathrm{~W}_{\mathrm{A}}} \\ & \cdot 45=\mathrm{i} \times 5 \cdot 12 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1} \times \frac{0 \cdot 3 \mathrm{~g}}{60 \mathrm{~g} \mathrm{~mol}^{-1}} \times \frac{1000}{30 \mathrm{~kg}} \\ & \mathrm{i}=0 \cdot 527 \\ & \alpha=\frac{1-\mathrm{i}}{1-\dfrac{1}{n}} \\ & \alpha=\frac{1-0 \cdot 527}{1-\dfrac{1}{2}}=0 \cdot 946 \text { or } 94 \cdot 6 \% \end{aligned} \]