Tarnish on copper is the compound cuo. a tarnished copper plate is placed in an aluminum pan of boiling water. when enough salt is added so that the solution conducts electricity, the tarnish disappears. imagine that the two halves of this redox reaction were separated and connected with a wire and a salt bridge.

calculate the standard cell potential given the following standard reduction potentials:

al3++3e-? al; e? =? 1.66 v
cu2++2e-? cu; e? =0.340 v