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Chemistry

L | Standard Electrode (Half-Cell) Potentials

ChemistryL | Standard Electrode (Half-Cell) Potentials

Standard Electrode (Half-Cell) Potentials
Half-Reaction E° (V)
Ag++eAgAg++eAg +0.7996
AgCl+eAg+ClAgCl+eAg+Cl +0.22233
[Ag(CN)2]+eAg+2CN[Ag(CN)2]+eAg+2CN −0.31
Ag2CrO4+2e2Ag+CrO42−Ag2CrO4+2e2Ag+CrO42− +0.45
[Ag(NH3)2]++eAg+2NH3[Ag(NH3)2]++eAg+2NH3 +0.373
[Ag(S2O3)2]3++eAg+2S2O32−[Ag(S2O3)2]3++eAg+2S2O32− +0.017
[AlF6]3−+3eAl+6F[AlF6]3−+3eAl+6F −2.07
Al3++3eAlAl3++3eAl −1.662
Am3++3eAmAm3++3eAm −2.048
Au3++3eAuAu3++3eAu +1.498
Au++eAuAu++eAu +1.692
Ba2++2eBaBa2++2eBa −2.912
Be2++2eBeBe2++2eBe −1.847
Br2(aq)+2e2BrBr2(aq)+2e2Br +1.0873
Ca2++2eCaCa2++2eCa −2.868
Ce3+3eCeCe3+3eCe −2.483
Ce4++eCe3+Ce4++eCe3+ +1.61
Cd2++2eCdCd2++2eCd −0.4030
[Cd(CN)4]2−+2eCd+4CN[Cd(CN)4]2−+2eCd+4CN −1.09
[Cd(NH3)4]2++2eCd+4NH3[Cd(NH3)4]2++2eCd+4NH3 −0.61
CdS+2eCd+S2−CdS+2eCd+S2− −1.17
Cl2+2e2ClCl2+2e2Cl +1.35827
ClO4+H2O+2eClO3+2OHClO4+H2O+2eClO3+2OH +0.36
ClO3+H2O+2eClO2+2OHClO3+H2O+2eClO2+2OH +0.33
ClO2+H2O+2eClO+2OHClO2+H2O+2eClO+2OH +0.66
ClO+H2O+2eCl+2OHClO+H2O+2eCl+2OH +0.89
ClO4+2H3O++2eClO3+3H2OClO4+2H3O++2eClO3+3H2O +1.189
ClO3+3H3O++2eHClO2+4H2OClO3+3H3O++2eHClO2+4H2O +1.21
HClO+H3O++2eCl+2H2OHClO+H3O++2eCl+2H2O +1.482
HClO+H3O++e12Cl2+2H2OHClO+H3O++e12Cl2+2H2O +1.611
HClO2+2H3O++2eHClO+3H2OHClO2+2H3O++2eHClO+3H2O +1.628
Co3++eCo2+(2mol//H2SO4)Co3++eCo2+(2mol//H2SO4) +1.83
Co2++2eCoCo2++2eCo −0.28
[Co(NH3)6]3++e[Co(NH3)6]2+[Co(NH3)6]3++e[Co(NH3)6]2+ +0.1
Co(OH)3+eCo(OH)2+OHCo(OH)3+eCo(OH)2+OH +0.17
Cr3+3eCrCr3+3eCr −0.744
Cr3++eCr2+Cr3++eCr2+ −0.407
Cr2++2eCrCr2++2eCr −0.913
[Cu(CN)2]+eCu+2CN[Cu(CN)2]+eCu+2CN −0.43
CrO42−+4H2O+3eCr(OH)3+5OHCrO42−+4H2O+3eCr(OH)3+5OH −0.13
Cr2O72−+14H3O++6e2Cr3++21H2OCr2O72−+14H3O++6e2Cr3++21H2O +1.232
[Cr(OH)4]+3eCr+4OH[Cr(OH)4]+3eCr+4OH −1.2
Cr(OH)3+3eCr+3OHCr(OH)3+3eCr+3OH −1.48
Cu2++eCu+Cu2++eCu+ +0.153
Cu2++2eCuCu2++2eCu +0.34
Cu++eCuCu++eCu +0.521
F2+2e2FF2+2e2F +2.866
Fe2++2eFeFe2++2eFe −0.447
Fe3++eFe2+Fe3++eFe2+ +0.771
[Fe(CN)6]3−+e[Fe(CN)6]4−[Fe(CN)6]3−+e[Fe(CN)6]4− +0.36
Fe(OH)2+2eFe+2OHFe(OH)2+2eFe+2OH −0.88
FeS+2eFe+S2−FeS+2eFe+S2− −1.01
Ga3++3eGaGa3++3eGa −0.549
Gd3++3eGdGd3++3eGd −2.279
12H2+eH12H2+eH −2.23
2H2O+2eH2+2OH2H2O+2eH2+2OH −0.8277
H2O2+2H3O++2e4H2OH2O2+2H3O++2e4H2O +1.776
2H3O++2eH2+2H2O2H3O++2eH2+2H2O 0.00
HO2+H2O+2e3OHHO2+H2O+2e3OH +0.878
Hf4++4eHfHf4++4eHf −1.55
Hg2++2eHgHg2++2eHg +0.851
2Hg2++2eHg22+2Hg2++2eHg22+ +0.92
Hg22++2e2HgHg22++2e2Hg +0.7973
[HgBr4]2−+2eHg+4Br[HgBr4]2−+2eHg+4Br +0.21
Hg2Cl2+2e2Hg+2ClHg2Cl2+2e2Hg+2Cl +0.26808
[Hg(CN)4]2−+2eHg+4CN[Hg(CN)4]2−+2eHg+4CN −0.37
[HgI4]2−+2eHg+4I[HgI4]2−+2eHg+4I −0.04
HgS+2eHg+S2−HgS+2eHg+S2− −0.70
I2+2e2II2+2e2I +0.5355
In3++3eInIn3++3eIn −0.3382
K++eKK++eK −2.931
La3++3eLaLa3++3eLa −2.52
Li++eLiLi++eLi −3.04
Lu3++3eLuLu3++3eLu −2.28
Mg2++2eMgMg2++2eMg −2.372
Mn2++2eMnMn2++2eMn −1.185
MnO2+2H2O+2eMn(OH)2+2OHMnO2+2H2O+2eMn(OH)2+2OH −0.05
MnO4+2H2O+3eMnO2+4OHMnO4+2H2O+3eMnO2+4OH +0.558
MnO2+4H++2eMn2++2H2OMnO2+4H++2eMn2++2H2O +1.23
MnO4+8H++5eMn2++4H2OMnO4+8H++5eMn2++4H2O +1.507
Na++eNaNa++eNa −2.71
Nd3++3eNdNd3++3eNd −2.323
Ni2++2eNiNi2++2eNi −0.257
[Ni(NH3)6]2++2eNi+6NH3[Ni(NH3)6]2++2eNi+6NH3 −0.49
NiO2+4H++2eNi2++2H2ONiO2+4H++2eNi2++2H2O +1.593
NiO2+2H2O+2eNi(OH)2+2OHNiO2+2H2O+2eNi(OH)2+2OH +0.49
NiS+2eNi+S2−NiS+2eNi+S2− +0.76
NO3+4H++3eNO+2H2ONO3+4H++3eNO+2H2O +0.957
NO3+3H++2eHNO2+H2ONO3+3H++2eHNO2+H2O +0.92
NO3+H2O+2eNO2+2OHNO3+H2O+2eNO2+2OH +0.10
Np3++3eNpNp3++3eNp −1.856
O2+2H2O+4e4OHO2+2H2O+4e4OH +0.401
O2+2H++2eH2O2 O2+2H++2eH2O2 +0.695
O2+4H++4e2H2OO2+4H++4e2H2O +1.229
Pb2++2ePbPb2++2ePb −0.1262
PbO2+SO42−+4H++2ePbSO4+2H2OPbO2+SO42−+4H++2ePbSO4+2H2O +1.69
PbS+2ePb+S2−PbS+2ePb+S2− −0.95
PbSO4+2ePb+SO42−PbSO4+2ePb+SO42− −0.3505
Pd2++2ePdPd2++2ePd +0.987
[PdCl4]2−+2ePd+4Cl[PdCl4]2−+2ePd+4Cl +0.591
Pt2++2ePtPt2++2ePt +1.20
[PtBr4]2−+2ePt+4Br[PtBr4]2−+2ePt+4Br +0.58
[PtCl4]2−+2ePt+4Cl[PtCl4]2−+2ePt+4Cl +0.755
[PtCl6]2−+2e[PtCl4]2−+2Cl[PtCl6]2−+2e[PtCl4]2−+2Cl +0.68
Pu3+3ePuPu3+3ePu −2.03
Ra2++2eRaRa2++2eRa −2.92
Rb++eRbRb++eRb −2.98
[RhCl6]3−+3eRh+6Cl[RhCl6]3−+3eRh+6Cl +0.44
S+2eS2−S+2eS2− −0.47627
S+2H++2eH2SS+2H++2eH2S +0.142
Sc3++3eScSc3++3eSc −2.09
Se+2H++2eH2SeSe+2H++2eH2Se −0.399
[SiF6]2−+4eSi+6F[SiF6]2−+4eSi+6F −1.2
SiO32−+3H2O+4eSi+6OHSiO32−+3H2O+4eSi+6OH −1.697
SiO2+4H++4eSi+2H2OSiO2+4H++4eSi+2H2O −0.86
Sm3++3eSmSm3++3eSm −2.304
Sn4++2eSn2+Sn4++2eSn2+ +0.151
Sn2++2eSnSn2++2eSn −0.1375
[SnF6]2−+4eSn+6F[SnF6]2−+4eSn+6F −0.25
SnS+2eSn+S2−SnS+2eSn+S2− −0.94
Sr2++2eSrSr2++2eSr −2.89
TeO2+4H++4eTe+2H2OTeO2+4H++4eTe+2H2O +0.593
Th4++4eThTh4++4eTh −1.90
Ti2++2eTiTi2++2eTi −1.630
U3++3eUU3++3eU −1.79
V2++2eVV2++2eV −1.19
Y3++3eYY3++3eY −2.37
Zn2++2eZnZn2++2eZn −0.7618
[Zn(CN)4]2−+2eZn+4CN[Zn(CN)4]2−+2eZn+4CN −1.26
[Zn(NH3)4]2++2eZn+4NH3[Zn(NH3)4]2++2eZn+4NH3 −1.04
Zn(OH)2+2eZn+2OHZn(OH)2+2eZn+2OH −1.245
[Zn(OH)4]2+2eZn+4OH[Zn(OH)4]2+2eZn+4OH −1.199
ZnS+2eZn+S2−ZnS+2eZn+S2− −1.40
Zr4+4eZrZr4+4eZr −1.539
Table L1
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