What happens if an electrochemical cell has electrodes with a different number of valence electrons?

A Daniell cell uses Zinc and Copper electrodes. ie, for every Zn atom oxidised, 2 electrons are released and exactly 1 Cu atom is reduced. What happens when electrodes are chosen such that the anode creates more or less electrons per oxidised atom than the cathode uses per reduced atom?

For Example, Aluminum (3 valence electrons) and Copper (2 valence electrons).

Answer:
The EMF of the cell is based upon the energy per unit of charge and is a function of the two half reactions. Changing one of the electrode will typically change one of the half reactions and thus the voltage of the cell.

The current is a function of the number of electrons which must move from the anode to the cathode to balance the half reactions.
2 Al >> 2 Al3+ + 6e- E° = + 1.676 V
3 Cu >> 3 Cu2+ + 6e- E° = - 0.337 V
The reaction that occurs is
2 Al + 3 Cu2+ >> 2 Al3+ + 3 Cu

for 2 Al 6 electrons are released and 3 Cu2+ are oxidized

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