For the disproportionation reaction,$2C{u}^{+}\rightleftharpoons cu+c{u}^{+2}$  at 298K. ln K(where K is the equilibrium constant) is $x\times {10}^{-1}{M}^{-1}$ . Here ‘X’ is  $\left(E^{0}c{u}^{+2}/cu=0.16V:E^{0}c{u}^{+}/cu=0.52V;\frac{RT}{F}=0.025\right)$