The answer should be 336 x 1014 Can you please explain how t

The answer should be 3.36 x 10^14. Can you please explain how to get this?

Calculate the equilibrium constant K for the following reaction at 25 degree C from standard electrode potentials. Note that the equation is not balanced. Cu(s) + Fe3+(aq) rightarrow Cu2+(aq) + Fe2(aq)

Solution

using the nerst equation at equilibrium and putting E as zero ..........we get E (STANDARD )= -.059/nln (Ka).......from standard electrode potentials of Cu and Fe........fo th e above reactions we get E (standard )=-9867V....PUTTING THE VALUES IN EQUATION WE GET K AS 3.36 x 10^14