Appendix L: Standard Electrode (Half-Cell) Potentials

Standard Electrode (Half-Cell) Potentials

Half-Reaction	E° (V)
$\ce{Ag+ + e- ⟶Ag}$	+0.7996
$\ce{AgCl + e- ⟶Ag + Cl-}$	+0.22233
$\ce{[Ag(CN)2]- + e- ⟶Ag + 2CN-}$	−0.31
$\ce{Ag2CrO4 + 2e- ⟶2Ag + CrO4^2-}$	+0.45
$\ce{[Ag(NH3)2]+ + e- ⟶Ag + 2NH3}$	+0.373
$\ce{[Ag(S2O3)2]^3+ + e- ⟶Ag + 2S2O3^2-}$	+0.017
$\ce{[AlF6]^3- + 3e- ⟶Al + 6F-}$	−2.07
$\ce{Al^3+ + 3e- ⟶Al}$	−1.662
$\ce{Am^3+ + 3e- ⟶Am}$	−2.048
$\ce{Au^3+ + 3e- ⟶Au}$	+1.498
$\ce{Au+ + e- ⟶Au}$	+1.692
$\ce{Ba^2+ + 2e- ⟶Ba}$	−2.912
$\ce{Be^2+ + 2e- ⟶Be}$	−1.847
$\ce{Br2}(aq) + \ce{2e-} ⟶\ce{2Br-}$	+1.0873
$\ce{Ca^2+ + 2e- ⟶Ca}$	−2.868
$\ce{Ce^3 + 3e- ⟶Ce}$	−2.483
$\ce{Ce^4+ + e- ⟶Ce^3+}$	+1.61
$\ce{Cd^2+ + 2e- ⟶Cd}$	−0.4030
$\ce{[Cd(CN)4]^2- + 2e- ⟶Cd + 4CN-}$	−1.09
$\ce{[Cd(NH3)4]^2+ + 2e- ⟶Cd + 4NH3}$	−0.61
$\ce{CdS + 2e- ⟶Cd + S^2-}$	−1.17
$\ce{Cl2 + 2e- ⟶2Cl-}$	+1.35827
$\ce{ClO4- + H2O + 2e- ⟶ClO3- + 2OH-}$	+0.36
$\ce{ClO3- + H2O + 2e- ⟶ClO2- + 2OH-}$	+0.33
$\ce{ClO2- + H2O + 2e- ⟶ClO- + 2OH-}$	+0.66
$\ce{ClO- + H2O + 2e- ⟶Cl- + 2OH-}$	+0.89
$\ce{ClO4- + 2H3O+ + 2e- ⟶ClO3- + 3H2O}$	+1.189
$\ce{ClO3- + 3H3O+ + 2e- ⟶HClO2 + 4H2O}$	+1.21
$\ce{HClO + H3O+ + 2e- ⟶Cl- + 2H2O}$	+1.482
$\ce{HClO + H3O+ + e- ⟶\dfrac{1}{2}Cl2 + 2H2O}$	+1.611
$\ce{HClO2 + 2H3O+ + 2e- ⟶HClO + 3H2O}$	+1.628
$\ce{Co^3+ + e- ⟶Co^2+ \:(2\:mol\,//\,H2SO4)}$	+1.83
$\ce{Co^2+ + 2e- ⟶Co}$	−0.28
$\ce{[Co(NH3)6]^3+ + e- ⟶[Co(NH3)6]^2+}$	+0.1
$\ce{Co(OH)3 + e- ⟶Co(OH)2 + OH-}$	+0.17
$\ce{Cr^3 + 3e- ⟶Cr}$	−0.744
$\ce{Cr^3+ + e- ⟶Cr^2+}$	−0.407
$\ce{Cr^2+ + 2e- ⟶Cr}$	−0.913
$\ce{[Cu(CN)2]- + e- ⟶Cu + 2CN-}$	−0.43
$\ce{CrO4^2- + 4H2O + 3e- ⟶ Cr(OH)3 + 5OH-}$	−0.13
$\ce{Cr2O7^2- + 14H3O+ + 6e- ⟶2Cr^3+ + 21H2O}$	+1.232
$\ce{[Cr(OH)4]- + 3e- ⟶Cr + 4OH-}$	−1.2
$\ce{Cr(OH)3 + 3e- ⟶Cr + 3OH-}$	−1.48
$\ce{Cu^2+ + e- ⟶Cu+}$	+0.153
$\ce{Cu^2+ + 2e- ⟶Cu}$	+0.34
$\ce{Cu+ + e- ⟶Cu}$	+0.521
$\ce{F2 + 2e- ⟶2F-}$	+2.866
$\ce{Fe^2+ + 2e- ⟶Fe}$	−0.447
$\ce{Fe^3+ + e- ⟶Fe^2+}$	+0.771
$\ce{[Fe(CN)6]^3- + e- ⟶[Fe(CN)6]^4-}$	+0.36
$\ce{Fe(OH)2 + 2e- ⟶Fe + 2OH-}$	−0.88
$\ce{FeS + 2e- ⟶Fe + S^2-}$	−1.01
$\ce{Ga^3+ + 3e- ⟶Ga}$	−0.549
$\ce{Gd^3+ + 3e- ⟶Gd}$	−2.279
$\ce{\dfrac{1}{2}H2 + e- ⟶H- }$	−2.23
$\ce{2H2O + 2e- ⟶H2 + 2OH-}$	−0.8277
$\ce{H2O2 + 2H3O+ + 2e- ⟶4H2O}$	+1.776
$\ce{2H3O+ + 2e- ⟶H2 + 2H2O}$	0.00
$\ce{HO2- + H2O + 2e- ⟶3OH-}$	+0.878
$\ce{Hf^4+ + 4e- ⟶Hf}$	−1.55
$\ce{Hg^2+ + 2e- ⟶Hg}$	+0.851
$\ce{2Hg^2+ + 2e- ⟶Hg2^2+}$	+0.92
$\ce{Hg2^2+ + 2e- ⟶2Hg}$	+0.7973
$\ce{[HgBr4]^2- + 2e- ⟶Hg + 4Br-}$	+0.21
$\ce{Hg2Cl2 + 2e- ⟶2Hg + 2Cl-}$	+0.26808
$\ce{[Hg(CN)4]^2- + 2e- ⟶Hg + 4CN-}$	−0.37
$\ce{[HgI4]^2- + 2e- ⟶Hg + 4I-}$	−0.04
$\ce{HgS + 2e- ⟶Hg + S^2-}$	−0.70
$\ce{I2 + 2e- ⟶2I-}$	+0.5355
$\ce{In^3+ + 3e- ⟶In}$	−0.3382
$\ce{K+ + e- ⟶K}$	−2.931
$\ce{La^3+ + 3e- ⟶La}$	−2.52
$\ce{Li+ + e- ⟶Li}$	−3.04
$\ce{Lu^3+ + 3e- ⟶Lu}$	−2.28
$\ce{Mg^2+ + 2e- ⟶Mg}$	−2.372
$\ce{Mn^2+ + 2e- ⟶Mn}$	−1.185
$\ce{MnO2 + 2H2O + 2e- ⟶Mn(OH)2 + 2OH-}$	−0.05
$\ce{MnO4- + 2H2O + 3e- ⟶MnO2 + 4OH-}$	+0.558
$\ce{MnO2 + 4H+ + 2e- ⟶Mn^2+ + 2H2O}$	+1.23
$\ce{MnO4- + 8H+ + 5e- ⟶Mn^2+ + 4H2O}$	+1.507
$\ce{Na+ + e- ⟶Na}$	−2.71
$\ce{Nd^3+ + 3e- ⟶Nd}$	−2.323
$\ce{Ni^2+ + 2e- ⟶Ni}$	−0.257
$\ce{[Ni(NH3)6]^2+ + 2e- ⟶Ni + 6NH3}$	−0.49
$\ce{NiO2 + 4H+ + 2e- ⟶Ni^2+ + 2H2O}$	+1.593
$\ce{NiO2 + 2H2O + 2e- ⟶Ni(OH)2 + 2OH-}$	+0.49
$\ce{NiS + 2e- ⟶Ni + S^2-}$	+0.76
$\ce{NO3- + 4H+ + 3e- ⟶NO + 2H2O}$	+0.957
$\ce{NO3- + 3H+ + 2e- ⟶HNO2 + H2O}$	+0.92
$\ce{NO3- + H2O + 2e- ⟶NO2- + 2OH-}$	+0.10
$\ce{Np^3+ + 3e- ⟶Np}$	−1.856
$\ce{O2 + 2H2O + 4e- ⟶4OH-}$	+0.401
$\ce{O2 + 2H+ + 2e- ⟶H2O2}$	+0.695
$\ce{O2 + 4H+ + 4e- ⟶2H2O}$	+1.229
$\ce{Pb^2+ + 2e- ⟶Pb}$	−0.1262
$\ce{PbO2 + SO4^2- + 4H+ + 2e- ⟶PbSO4 + 2H2O}$	+1.69
$\ce{PbS + 2e- ⟶Pb + S^2-}$	−0.95
$\ce{PbSO4 + 2e- ⟶Pb + SO4^2-}$	−0.3505
$\ce{Pd^2+ + 2e- ⟶Pd}$	+0.987
$\ce{[PdCl4]^2- + 2e- ⟶Pd + 4Cl-}$	+0.591
$\ce{Pt^2+ + 2e- ⟶Pt}$	+1.20
$\ce{[PtBr4]^2- + 2e- ⟶Pt + 4Br-}$	+0.58
$\ce{[PtCl4]^2- + 2e- ⟶Pt + 4Cl-}$	+0.755
$\ce{[PtCl6]^2- + 2e- ⟶[PtCl4]^2- + 2Cl-}$	+0.68
$\ce{Pu^3 + 3e- ⟶Pu}$	−2.03
$\ce{Ra^2+ + 2e- ⟶Ra}$	−2.92
$\ce{Rb+ + e- ⟶Rb}$	−2.98
$\ce{[RhCl6]^3- + 3e- ⟶Rh + 6Cl-}$	+0.44
$\ce{S + 2e- ⟶S^2-}$	−0.47627
$\ce{S + 2H+ + 2e- ⟶H2S}$	+0.142
$\ce{Sc^3+ + 3e- ⟶Sc}$	−2.09
$\ce{Se + 2H+ + 2e- ⟶H2Se}$	−0.399
$\ce{[SiF6]^2- + 4e- ⟶Si + 6F-}$	−1.2
$\ce{SiO3^2- + 3H2O + 4e- ⟶Si + 6OH-}$	−1.697
$\ce{SiO2 + 4H+ + 4e- ⟶Si + 2H2O}$	−0.86
$\ce{Sm^3+ + 3e- ⟶Sm}$	−2.304
$\ce{Sn^4+ + 2e- ⟶Sn^2+}$	+0.151
$\ce{Sn^2+ + 2e- ⟶Sn}$	−0.1375
$\ce{[SnF6]^2- + 4e- ⟶Sn + 6F-}$	−0.25
$\ce{SnS + 2e- ⟶Sn + S^2-}$	−0.94
$\ce{Sr^2+ + 2e- ⟶Sr}$	−2.89
$\ce{TeO2 + 4H+ + 4e- ⟶Te + 2H2O}$	+0.593
$\ce{Th^4+ + 4e- ⟶Th}$	−1.90
$\ce{Ti^2+ + 2e- ⟶Ti}$	−1.630
$\ce{U^3+ + 3e- ⟶U}$	−1.79
$\ce{V^2+ + 2e- ⟶V}$	−1.19
$\ce{Y^3+ + 3e- ⟶Y}$	−2.37
$\ce{Zn^2+ + 2e- ⟶Zn}$	−0.7618
$\ce{[Zn(CN)4]^2- + 2e- ⟶Zn + 4CN-}$	−1.26
$\ce{[Zn(NH3)4]^2+ + 2e- ⟶Zn + 4NH3}$	−1.04
$\ce{Zn(OH)2 + 2e- ⟶Zn + 2OH-}$	−1.245
$\ce{[Zn(OH)4]^2 + 2e- ⟶Zn + 4OH-}$	−1.199
$\ce{ZnS + 2e- ⟶Zn + S^2-}$	−1.40
$\ce{Zr^4 + 4e- ⟶Zr}$	−1.539