Chapter 18, Problem 53E

In a solution that is 0.0500M in ${\left[\text{Cu}{\left(\text{CN}\right)}_4\right]}^{2-}$ and 0.80M in free ${\text{CN}}^{\text{-}}$ ; the concentration of ${\text{Cu}}^{-}$ is $6.1\times {10}^{-22}\text{M}$ . Calculate of $K_t$ of ${\left[\text{Cu}{\left(\text{CN}\right)}_{\text{4}}\right]}^{\text{2-}}$ .

   ${\text{Cu}}^{+}\left(\text{aq}\right)+4{\text{CN}}^{\text{-}}\left(\text{aq}\right)\rightleftharpoons {\left[\text{Cu}\left({\text{CN}}_4\right)\right]}^{3-}\left(\text{aq}\right)K_f=?$