Question

A galvanic (voltaic) cell consists of an electrode composed of nickel in a 1.0 M nickel(II) ion solution and another electrode composed of gold in a 1.0 M gold(III) ion solution, connected by a salt bridge. Calculate the standard potential for this cell at 25 °C.

Answer 1

Standard potential for this cell, E°cell = E°cathode-E°anode

Now, E°(Au3+/Au) = 1.50 V

E°(Ni2+/Ni) = -0.23 V

Since Au has high reduction potential (E°) thus it will reduce at cathode and Ni will oxidize at anode.

E°cell = E°(Au3+/Au) - E°(Ni2+/Ni)

= 1.50-(-0.23)

= 1.73 V