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Half-Reaction | E° (V) |
---|---|
Ac3+ + 3e−→ Ac | −2.20 |
Ag+ + e−→ Ag | 0.7996 |
AgBr + e−→ Ag + Br− | 0.07133 |
AgCl + e−→ Ag + Cl− | 0.22233 |
Ag2CrO4 + 2e−→ 2Ag + CrO42− | 0.4470 |
AgI + e−→ Ag + I− | −0.15224 |
Ag2S + 2e−→ 2Ag + S2− | −0.691 |
Ag2S + 2H+ + 2e−→ 2Ag + H2S | −0.0366 |
AgSCN + e−→ Ag + SCN− | 0.08951 |
Al3+ + 3e−→ Al | −1.662 |
Al(OH)4− + 3e−→ Al + 4OH− | −2.328 |
Am3+ + 3e−→ Am | −2.048 |
As + 3H+ + 3e−→ AsH3 | −0.608 |
H3AsO4 + 2H+ + 2e−→ HAsO2 + 2H2O | 0.560 |
Au+ + e−→ Au | 1.692 |
Au3+ + 3e−→ Au | 1.498 |
H3BO3 + 3H+ + 3e−→ B + 3H2O | −0.8698 |
Ba2+ + 2e−→ Ba | −2.912 |
Be2+ + 2e−→ Be | −1.847 |
Bi3+ + 3e−→ Bi | 0.308 |
BiO+ + 2H+ + 3e−→ Bi + H2O | 0.320 |
Br2(aq) + 2e−→ 2Br− | 1.0873 |
Br2(l) + 2e−→ 2Br− | 1.066 |
BrO3− + 6H+ + 5e−→ Br2 + 3H2O | 1.482 |
BrO3− + 6H+ + 6e−→ Br− + 3H2O | 1.423 |
CO2 + 2H+ + 2e−→ HCO2H | −0.199 |
Ca2+ + 2e−→ Ca | −2.868 |
Ca(OH)2 + 2e−→ Ca + 2OH− | −3.02 |
Cd2+ + 2e−→ Cd | −0.4030 |
CdSO4 + 2e−→ Cd + SO42− | −0.246 |
Cd(OH)42− + 2e−→ Cd + 4OH− | −0.658 |
Ce3+ + 3e−→ Ce | −2.336 |
Ce4− + e−→ Ce3+ | 1.72 |
Cl2(g) + 2e−→ 2Cl− | 1.35827 |
HClO + H+ + e−→ Cl2 + H2O | 1.611 |
HClO + H+ + 2e−→ Cl− + H2O | 1.482 |
ClO− + H2O + 2e−→ Cl− + 2OH− | 0.81 |
ClO3− + 6H+ + 5e−→ Cl2 + 3H2O | 1.47 |
ClO3− + 6H+ + 6e−→ Cl− + 3H2O | 1.451 |
ClO4− + 8H+ + 7e−→ Cl2 + 4H2O | 1.39 |
ClO4− + 8H+ + 8e−→ Cl− + 4H2O | 1.389 |
Co2+ + 2e−→ Co | −0.28 |
Co3+ + e−→ Co2+ | 1.92 |
Cr2+ + 2e−→ Cr | −0.913 |
Cr3+ + e−→ Cr2+ | −0.407 |
Cr3+ + 3e−→ Cr | −0.744 |
Cr2O7− + 14H+ + 6e−→ 2Cr3+ + 7H2O | 1.232 |
CrO42− + 4H2O + 3e−→ Cr(OH)3 + 5OH− | −0.13 |
Cs+ + e−→ Cs | −3.026 |
Cu+ + e−→ Cu | 0.521 |
Cu2+ + e−→ Cu+ | 0.153 |
Cu2+ + 2e−→ Cu | 0.3419 |
CuI2− + e−→ Cu + 2I− | 0.00 |
Cu2O + H2O + 2e−→ 2Cu + 2OH− | −0.360 |
Dy3+ + 3e−→ Dy | −2.295 |
Er3+ + 3e−→ Er | −2.331 |
Es3+ + 3e−→ Es | −1.91 |
Eu2+ + 2e−→ Eu | −2.812 |
Eu3+ + 3e−→ Eu | −1.991 |
F2 + 2e−→ 2F− | 2.866 |
Fe2+ + 2e−→ Fe | −0.447 |
Fe3+ + 3e−→ Fe | −0.037 |
Fe3+ + e−→ Fe2+ | 0.771 |
[Fe(CN)6]3− + e−→ [Fe(CN)6]4− | 0.358 |
Fe(OH)3 + e−→ Fe(OH)2 + OH− | −0.56 |
Fm3+ + 3e−→ Fm | −1.89 |
Fm2+ + 2e−→ Fm | −2.30 |
Ga3+ + 3e−→ Ga | −0.549 |
Gd3+ + 3e−→ Gd | −2.279 |
Ge2+ + 2e−→ Ge | 0.24 |
Ge4+ + 4e−→ Ge | 0.124 |
2H+ + 2e−→ H2 | 0.00000 |
H2 + 2e−→ 2H− | −2.23 |
2H2O + 2e−→ H2 + 2OH− | −0.8277 |
H2O2 + 2H+ + 2e−→ 2H2O | 1.776 |
Hf4+ + 4e−→ Hf | −1.55 |
Hg2+ + 2e−→ Hg | 0.851 |
2Hg2+ + 2e−→ Hg22+ | 0.920 |
Hg2Cl2 + 2e−→ 2Hg + 2Cl− | 0.26808 |
Ho2+ + 2e−→ Ho | −2.1 |
Ho3+ + 3e−→ Ho | −2.33 |
I2 + 2e−→ 2I− | 0.5355 |
I3− + 2e−→ 3I− | 0.536 |
2IO3− + 12H+ + 10e−→ I2 + 6H2O | 1.195 |
IO3− + 6H+ + 6e−→ I− + 3H2O | 1.085 |
In+ + e−→ In | −0.14 |
In3+ + 2e−→ In+ | −0.443 |
In3+ + 3e−→ In | −0.3382 |
Ir3+ + 3e−→ Ir | 1.156 |
K+ + e−→ K | −2.931 |
La3+ + 3e−→ La | −2.379 |
Li+ + e−→ Li | −3.0401 |
Lr3+ + 3e−→ Lr | −1.96 |
Lu3+ + 3e−→ Lu | −2.28 |
Md3+ + 3e−→ Md | −1.65 |
Md2+ + 2e−→ Md | −2.40 |
Mg2+ + 2e−→ Mg | −2.372 |
Mn2+ + 2e−→ Mn | −1.185 |
MnO2 + 4H+ + 2e−→ Mn2+ + 2H2O | 1.224 |
MnO4− + 8H+ + 5e−→ Mn2+ + 4H2O | 1.507 |
MnO4− + 2H2O + 3e−→ MnO2 + 4OH− | 0.595 |
Mo3+ + 3e−→ Mo | −0.200 |
N2 + 2H2O + 6H+ + 6e−→ 2NH4OH | 0.092 |
HNO2 + H+ + e−→ NO + H2O | 0.983 |
NO3− + 4H+ + 3e−→ NO + 2H2O | 0.957 |
Na+ + e−→ Na | −2.71 |
Nb3+ + 3e−→ Nb | −1.099 |
Nd3+ + 3e−→ Nd | −2.323 |
Ni2+ + 2e−→ Ni | −0.257 |
No3+ + 3e−→ No | −1.20 |
No2+ + 2e−→ No | −2.50 |
Np3+ + 3e−→ Np | −1.856 |
O2 + 2H+ + 2e−→ H2O2 | 0.695 |
O2 + 4H+ + 4e−→ 2H2O | 1.229 |
O2 + 2H2O + 2e−→ H2O2 + 2OH− | −0.146 |
O3 + 2H+ + 2e−→ O2 + H2O | 2.076 |
OsO4 + 8H+ + 8e−→ Os + 4H2O | 0.838 |
P + 3H2O + 3e−→ PH3(g) + 3OH− | −0.87 |
PO43− + 2H2O + 2e−→ HPO32− + 3OH− | −1.05 |
Pa3+ + 3e−→ Pa | −1.34 |
Pa4+ + 4e−→ Pa | −1.49 |
Pb2+ + 2e−→ Pb | −0.1262 |
PbO + H2O + 2e−→ Pb + 2OH− | −0.580 |
PbO2 + SO42− + 4H+ + 2e−→ PbSO4 + 2H2O | 1.6913 |
PbSO4 + 2e−→ Pb + SO42− | −0.3588 |
Pd2+ + 2e−→ Pd | 0.951 |
Pm3+ + 3e−→ Pm | −2.30 |
Po4+ + 4e−→ Po | 0.76 |
Pr3+ + 3e−→ Pr | −2.353 |
Pt2+ + 2e−→ Pt | 1.18 |
[PtCl4]2− + 2e−→ Pt + 4Cl− | 0.755 |
Pu3+ + 3e−→ Pu | −2.031 |
Ra2+ + 2e−→ Ra | −2.8 |
Rb+ + e−→ Rb | −2.98 |
Re3+ + 3e−→ Re | 0.300 |
Rh3+ + 3e−→ Rh | 0.758 |
Ru3+ + e−→ Ru2+ | 0.2487 |
S + 2e−→ S2− | −0.47627 |
S + 2H+ + 2e−→ H2S(aq) | 0.142 |
2S + 2e−→ S22− | −0.42836 |
H2SO3 + 4H+ + 4e−→ S + 3H2O | 0.449 |
SO42− + H2O + 2e−→ SO32− + 2OH− | −0.93 |
Sb + 3H+ + 3e−→ SbH3 | −0.510 |
Sc3+ + 3e−→ Sc | −2.077 |
Se + 2e−→ Se2− | −0.924 |
Se + 2H+ + 2e−→ H2Se | −0.082 |
SiF62− + 4e−→ Si + 6F− | −1.24 |
Sm3+ + 3e−→ Sm | −2.304 |
Sn2+ + 2e−→ Sn | −0.1375 |
Sn4+ + 2e−→ Sn2+ | 0.151 |
Sr2+ + 2e−→ Sr | −2.899 |
Ta3+ + 3e−→ Ta | −0.6 |
TcO4− + 4H+ + 3e−→ TcO2 + 2H2O | 0.782 |
TcO4− + 8H+ + 7e−→ Tc + 4H2O | 0.472 |
Tb3+ + 3e−→ Tb | −2.28 |
Te + 2e−→ Te2− | −1.143 |
Te4+ + 4e−→ Te | 0.568 |
Th4+ + 4e−→ Th | −1.899 |
Ti2+ + 2e−→ Ti | −1.630 |
Tl+ + e−→ Tl | −0.336 |
Tl3+ + 2e−→ Tl+ | 1.252 |
Tl3+ + 3e−→ Tl | 0.741 |
Tm3+ + 3e−→ Tm | −2.319 |
U3+ + 3e−→ U | −1.798 |
VO2+ + 2H+ + e−→ VO2+ + H2O | 0.991 |
V2O5 + 6H+ + 2e−→ 2VO2+ + 3H2O | 0.957 |
W2O5 + 2H+ + 2e−→ 2WO2 + H2O | −0.031 |
XeO3 + 6H+ + 6e−→ Xe + 3H2O | 2.10 |
Y3+ + 3e−→Y | −2.372 |
Yb3+ + 3e−→Yb | −2.19 |
Zn2+ + 2e−→ Zn | −0.7618 |
Zn(OH)42− + 2e−→ Zn + 4OH− | −1.199 |
Zn(OH)2 + 2e−→ Zn + 2OH− | −1.249 |
ZrO2 + 4H+ + 4e−→ Zr + 2H2O | −1.553 |
Zr4+ + 4e−→ Zr | −1.45 |
Source of data: CRC Handbook of Chemistry and Physics, 84th Edition (2004).