In a galvanic cell (aka a voltaic cell), you have zinc and copper reacting. The shorthand version of these reactions is Zn|Zn⁺²| |Cu⁺²|Cu. Find the potential energy (E _cell°) of this battery.

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Solution is as follows: The short hand reaction Zn|Zn⁺² yields a halF^-reaction of Zn -> Zn⁺² + 2 e-. This is an oxidation reaction because the zinc's charge increases and it loses electrons. The corresponding half reaction for copper is Cu⁺² + 2 e- -> Cu, which is a reduction reaction. The total reaction happening in this cell is: Zn + Cu⁺² --> Zn⁺² + Cu Use the equation E _cell °= E_oxidation° + E_reduction° Look up the standard reduction potential (V) for both half reactions. Zn --> Zn⁺² + 2 e- has a V = -0.76V Cu⁺² + 2 e- --> Cu has a V = 0.34V Adding those values yields E _cell °= -0.42V

In a Galvanic Cell (Aka a Voltaic Cell), You Have