The freezing point of benzene decreases by 0.45^° C when 0.2 g of acetic acid is added to 20 g of benzene. If acetic acid associates to form a dimer…

The freezing point of benzene decreases by $\displaystyle 0.45^{\circ} \mathrm{C}$ when $\displaystyle 0.2$ g of acetic acid is added to $\displaystyle 20$ g of benzene. If acetic acid associates to form a dimer in benzene, percentage association of acetic acid in benzene will be : $\displaystyle \left(\mathrm{K}_{\mathrm{f}}\right.$ for benzene $\displaystyle \left.=5.12 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$