[lillybeans]

Cu(s) | Cu2+ (aq), SO4 2-(aq) | Cu(s)

And the question asks to find the minimum voltage needed to induce the electrochemical change.

I think this is a tricky question but I'm not sure. If you compare all the reduction potentials, you will find that Cu2+ has the largest reduction potential at the cathode, and Cu(s) has the largest oxidation potential at the anode. Theoretically, the reduction of Cu2+ is the preferred reaction at the cathode, and the oxidation of Cu(s) is the preferred reaction at the anode. HOWEVER, if both electrodes are copper, the answer will be 0 volts. But the answer can't be 0 volts, because if E cell is 0, then there will be no electron flow since the two electrodes are the same. So.. how to go about this question?

P.S. The textbook says the answer is 0 volts, but it just doesn't make any sense to me. If 0 volts is required for this reaction to happen, then is this spontaneous or not? Also, a similar question that I had: If electrolysis can induce reactions with a negative E-cell (non-spontaneous reaction) to occur by applying a voltage (battery or whatever), then can electrolysis also induce reactions with an E-cell of ZERO? (same element at both electrodes)