Chapter 16, Problem 16.117SP

Dissolution of $5.0\times {\text{10}}^{\text{-3}}$ mol of $\text{Cr}{\left(\text{OH}\right)}_3$ in $\text{1}.0\text{ L}$ of $\text{1}.0\text{ M NaOH}$ gives a solution of the complex ion $\text{Cr}{\left(\text{OH}\right)}_4{}^{-}\left({\text{K}}_{\text{f}}\text{ = 8}\times \text{1}{0}^{\text{29}}\right)$ . What fraction of the chromium in such a solution is present as uncomplexed ${\text{Cr}}^{3+}$ ?