The standard electrode potential corresponding to the reduction `Cr^(3+)+ e to Cr^(2+)` is `E^@=-0.407` volt. IF excess `Fe(s)` is added to a solution in which `[Cr^(3+)]=1M`, what will be `[Fe^(2+)]` when equilibrium is established at `25^@C`
`[Fe (s)+2Cr^(3+) leftrightarrow Fe^(2+)+ 2Cr^(2+)]`

Explanation

`[Fe^(2+)]=0.42M]`