Cathode (Reduction)
Half-Reaction | Standard Potential
E° (volts) |
| Li+(aq) + e- -> Li(s) | -3.04 |
| K+(aq) + e- -> K(s) | -2.92 |
| Ca2+(aq) + 2e- -> Ca(s) | -2.76 |
| Na+(aq) + e- -> Na(s) | -2.71 |
| Mg2+(aq) + 2e- -> Mg(s) | -2.38 |
| Al3+(aq) + 3e- -> Al(s) | -1.66 |
| 2H2O(l) + 2e- -> H2(g) + 2OH-(aq) | -0.83 |
| Zn2+(aq) + 2e- -> Zn(s) | -0.76 |
| Cr3+(aq) + 3e- -> Cr(s) | -0.74 |
| Fe2+(aq) + 2e- -> Fe(s) | -0.41 |
| Cd2+(aq) + 2e- -> Cd(s) | -0.40 |
| Ni2+(aq) + 2e- -> Ni(s) | -0.23 |
| Sn2+(aq) + 2e- -> Sn(s) | -0.14 |
| Pb2+(aq) + 2e- -> Pb(s) | -0.13 |
| Fe3+(aq) + 3e- -> Fe(s) | -0.04 |
| 2H+(aq) + 2e- -> H2(g) | 0.00 |
| Sn4+(aq) + 2e- -> Sn2+(aq) | 0.15 |
| Cu2+(aq) + e- -> Cu+(aq) | 0.16 |
| ClO4-(aq) + H2O(l) + 2e- -> ClO3-(aq) + 2OH-(aq) | 0.17 |
| AgCl(s) + e- -> Ag(s) + Cl-(aq) | 0.22 |
| Cu2+(aq) + 2e- -> Cu(s) | 0.34 |
| ClO3-(aq) + H2O(l) + 2e- -> ClO2-(aq) + 2OH-(aq) | 0.35 |
| IO-(aq) + H2O(l) + 2e- -> I-(aq) + 2OH-(aq) | 0.49 |
| Cu+(aq) + e- -> Cu(s) | 0.52 |
| I2(s) + 2e- -> 2I-(aq) | 0.54 |
| ClO2-(aq) + H2O(l) + 2e- -> ClO-(aq) + 2OH-(aq) | 0.59 |
| Fe3+(aq) + e- -> Fe2+(aq) | 0.77 |
| Hg22+(aq) + 2e- -> 2Hg(l) | 0.80 |
| Ag+(aq) + e- -> Ag(s) | 0.80 |
| Hg2+(aq) + 2e- -> Hg(l) | 0.85 |
| ClO-(aq) + H2O(l) + 2e- -> Cl-(aq) + 2OH-(aq) | 0.90 |
| 2Hg2+(aq) + 2e- -> Hg22+(aq) | 0.90 |
| NO3-(aq) + 4H+(aq) + 3e- -> NO(g) + 2H2O(l) | 0.96 |
| Br2(l) + 2e- -> 2Br-(aq) | 1.07 |
| O2(g) + 4H+(aq) + 4e- -> 2H2O(l) | 1.23 |
| Cr2O72-(aq) + 14H+(aq) + 6e- -> 2Cr3+(aq) + 7H2O(l) | 1.33 |
| Cl2(g) + 2e- -> 2Cl-(aq) | 1.36 |
| Ce4+(aq) + e- -> Ce3+(aq) | 1.44 |
| MnO4-(aq) + 8H+(aq) + 5e- -> Mn2+(aq) + 4H2O(l) | 1.49 |
| H2O2(aq) + 2H+(aq) + 2e- -> 2H2O(l) | 1.78 |
| Co3+(aq) + e- -> Co2+(aq) | 1.82 |
| S2O82-(aq) + 2e- -> 2SO42-(aq) | 2.01 |
| O3(g) + 2H+(aq) + 2e- -> O2(g) + H2O(l) | 2.07 |
| F2(g) + 2e- -> 2F-(aq) | 2.87 |