Acetic acid is a weak acid that ionizes in solution as follows:
$$
\mathrm{CH}_3 \mathrm{COOH}(a q) \rightleftharpoons \mathrm{CH}_3 \mathrm{COO}^{-}(a q)+\mathrm{H}^{+}(a q)
$$
If the freezing point of a $0.106 m \mathrm{CH}_3 \mathrm{COOH}$ solution is $-0.203^{\circ} \mathrm{C}$, calculate the percent of the acid that has undergone ionization.