Standard Reduction Potentials at 25°C

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Half-Reaction E° (V)
F2(g) + 2e- <==> 2F- +2.87
PbO2(s) + SO42-(aq) + 4H+ + 2e- <==> PbSO4(s) + H2O +1.69
2HOCl(aq) + 2H+(aq) + 2e- <==> Cl2(g) + 2H20 +1.63
MnO4-(aq) + 8H+(aq) + 5e- <==> Mn2+(aq) + 4H20 +1.51
PbO2(s) + 4H+(aq) + 2e- <==> Pb2+(aq) + 2H2O +1.46
BrO3-(aq) + 6H+(aq) + 6e- <==> Br-(aq) + 3H2O +1.44
Au3+ (aq) + 3e- <==> Au(s) +1.42
Cl2 (g) + 2e- <==> Cl-(aq) +1.36
O2(g) + 4H+(aq) + 4e- <==> 2H2O +1.23
Br2 (aq) + 2e- <==> 2Br-(aq) +1.07
NO3-(aq) + 4H+(aq) + 3e <==> NO(g) + 2H2O +0.96
Ag+(aq) + e- <==> Ag(s) +0.80
Fe3+(aq) + e- <==> Fe2+(aq) +0.77
I2(s) + 2e- <==> 2I-(aq) +0.54
NiO2(aq) + 4H+(aq) + 3e- <==> Ni(OH)2(s) + 2OH-(aq) +0.49
Cu2+(aq) + 2e- <==> Cu(s) +0.34
SO42- + 4H+(aq) + 2e- <==> H2SO3(aq) + H2O +0.17
2H+ (aq) + 2e- <==> H2(g) 0.00
Sn2+ (aq) + 2e- <==> Ni(s) -0.14
Ni2+ (aq) + 2e- <==> Ni(s) -0.25
Co2+ (aq) + 2e- <==> Co(s) -0.28
PbSO4 (s) + 2e- <==> Pb(s) + SO42- -0.36
Cd2+ (aq) + 2e- <==> Cd(s) -0.40
Fe2+ (aq) + 2e- <==> Fe(s) -0.44
Cr3+ (aq) + 3e- <==> Cr(s) -0.74
Zn2+ (aq) + 2e- <==> Zn(s) -0.83
2H2O (aq) + 2e- <==> H2(g) + 2OH-(aq) -1.66
Mg2+ (aq) + 2e- <==> Mg(s) -2.37
Na+ (aq) + e- <==> Na(s) -2.71
Ca2+ (aq) + 2e- <==> Ca(s) -2.76
K+ (aq) + e- <==> K(s) -2.92
Li+ (aq) + e- <==> Li(s) -3.05