Given the data at ${25}^{0}C$ ,

$Ag+I^{-}\stackrel{}{\to }AgI+e^{-};E^0=+0.152$ V

$Ag\stackrel{}{\to }A{g}^{+}+e^{-};E^0=-0.8$ V

What is the value of log $K_{sp}$  for $AgI$  ?

$\left(2.303\frac{RT}{F}=0.059V\right)$

$GivenAg\stackrel{}{\to }A{g}^{+}+e^{-};E^0=-0.8\Rightarrow \left(1\right)$

$\underset{\_}{Ag+I^{-}\stackrel{}{\to }AgI+e^{-};E^0=+0.152\Rightarrow \left(2\right)}$

    $\left(1\right)-\left(2\right)\Rightarrow AgI\stackrel{}{\to }A{g}^{+}+I^{-};E^0=-0.952V$

                                   $E^0=\frac{2.303RT}{nF}.\log K_{sp}$

                             $-0.952=\frac{0.059}{1}.\log K_{sp}$

                             $\log .K_{sp}=-\frac{0.952}{0.59}\approx -16.108$