Calculate the standard electrode potential of the `Ni^(2+)//Ni` electrode , if the cell potential potential of the cell,
`Ni//N^(2+)(0.01 M)//Cu is 0.59" V ". "Given" E_(Cu^(2+)//Cu)^(@)=+0.34 " V "`

Explanation

The cell is `Ni | Ni^(2+) (1M) || Cu^(2+) (1M) |Cu`
The e.m.f of the cell
`E_(cell)^(Theta) = E_(H)^(Theta) = E_(L)^(Theta) = E^(Theta) (Cu^(2+) |Cu) - E^(Theta) (Ni^(2+) | Ni)`
Here , `E_(cell)^(Theta) = 0.59 V , E^(Theta) (Cu^(2+) Cu) = 0.34` V
`therefore 0.59 = 0.34 - E^(Theta) (Ni^(2+) |Ni)`
or `E^(Theta) (Ni^(2+) | Ni) = 0.34 - 0.59 = -0.25 V`.