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I. Electrolysis
� Driving a nonspon. redox rxn with electrical current.
� Cu(s) + Zn2+(aq) à Zn(s) + Cu2+(aq)
� E° = –1.10 V
� Overpotential: excess V above V calculated w/ E° that is req’d for electrolysis.
I. Electrolysis
� Faraday’s Law: Amt. of chem. change produced proportional to the amt. of current passed through it.
� Ex. #1: How much Cu(s) can be deposited if you run a current for 3.0 min. @ 2.0 amps.
III. Batteries
� Dry Cell Batteries:
An: Zn(s) à Zn2+(aq) + 2 e–
Cat: 2 MnO2(s) + 2 NH4+(aq) + 2 e–
à Mn2O3(s) + 2 NH3(g) + H2O(l)
III. Batteries
� Alkaline Batteries:
� An: Zn(s) + 2 OH–(aq) à Zn(OH)2(s) + 2 e–
� Cat: 2 MnO2(s) + 2 H2O(l) + 2 e– à
2 MnO(OH)(s) + 2 OH–(aq)