Chemistry - Liquid Solution Question with Solution | TestHub

Acetic acid dissociates as $C{H}_{3}COOH\rightleftharpoons C{H}_{3}CO{O}^{-}+H^{+}$.

The number of ions produced per molecule is $n=2$.

The degree of dissociation is $\alpha =1.35\%=0.0135$.

The van't Hoff factor $i$ is given by $i=1+(n-1)\alpha$.

$i=1+(2-1)\times 0.0135=1.0135$

The depression in freezing point is $\Delta T_f=i\times K_f\times m$.

Substituting the given values:

$\Delta T_f=1.0135\times 1.86\times 0.1$

$\Delta T_f=0.188511^{\circ }\text{C}\approx 0.189^{\circ }\text{C}$

Answer: $0.189$ ${}^{\circ }$C