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Galvanic Cells and Faraday's Laws

1. Diagram the following galvanic cell (or just tell what it would look like), indicating the direction of flow of electrons in the external circuit and the motion of ions in the salt bridge. Ni(s)lNi2+(aq)llHCl(aq)lH2(g)lPt(s). Also write a balanced equation for the overall reaction in this cell.

2. In the Hall-Heroult for the electrolytic production of aluminum, Al3+ ions from Al2O3 dissolved in molten cryolite (Na3AlF6) are reduced to Al(l) while carbon is oxidized to CO2 by reaction with oxide ions.
(a)Write balanced equations for the half reactions at the anode and at the cathode and for the overall cell reaction.
(b)If a current of 50,000 A is passed through the cell for a period of 24 hours, what mass of aluminum will be recoverd?

Solution Preview

1) Overall Reaction: Ni (s) + 2H+(aq) Ni2+(aq) + H2 (g)

2) a) cathode reaction: Al3+ + 3e- ---> Al(l)

anode ...

Solution Summary

Solution includes complete diagram for (1) and chemical equations for (1) and (2).