electrochemical cells. spontaneous redox reaction - zn + cu 2+ zn (s) + cu 2+ (aq) zn 2+ (aq) + cu...
Post on 21-Dec-2015
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Electrochemical Cells
Spontaneous Redox Reaction - Zn + Cu2+
Zn(s) + Cu2+(aq) Zn2+(aq) + Cu(s)
Non-Spontaneous Redox Reaction - Water
2 H2O(l) 2 H2(g) + O2(g)
Battery Construction - Zn + Cu2+
Zn|Zn2+||Cu2+|Cu
Volta’s Pile
Commercial Cells - Le Clanche (Dry) Cell
Zn | Zn2+, NH4Cl, MnO2 | C
Zn + 2 MnO2 + 2 NH4+ Mn2O3 + 2 NH3 + H2O + Zn2+
Commercial Cells - Lead Storage Battery
Pb(s) | PbSO4(s) | H2SO4(aq) | PbSO4(s) | PbO2(s) | Pb(s)
Pb + PbO2 + 2 H2SO4 2 PbSO4 + 2 H2O
Commercial Cells - Nickel-Cadmium Battery
Zn | ZnO2 | OH- | Hg | HgO
Zn + HgO ZnO + Hg
Battery Connections
Series Connection
Parallel Connection
Historical Origin of Sign Convention
Cell Conventions
Standard Hydrogen Electrode (SHE)
SHE || Cathode
Pt(s) | H2(g,f=1) | H+(aq,a=1) || Cathode
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