Standard Electrode (Half-Cell) Potentials, Front matter | Chemistry 2e

Learning objectives

Standard Electrode (Half-Cell) Potentials
Half-Reaction	E° (V)
${Ag}^{+} + e^{-} ⟶ Ag$	+0.7996
$AgCl + e^{-} ⟶ Ag + {Cl}^{-}$	+0.22233
${[Ag {(CN)}_{2}]}^{-} + e^{-} ⟶ Ag + 2 {CN}^{-}$	−0.31
${Ag}_{2} {CrO}_{4} + 2 e^{-} ⟶ 2 Ag + {CrO}_{4}^{2−}$	+0.45
${[Ag {({NH}_{3})}_{2}]}^{+} + e^{-} ⟶ Ag + 2 {NH}_{3}$	+0.373
${[Ag {(S_{2} O_{3})}_{2}]}^{3+} + e^{-} ⟶ Ag + {2S}_{2} O_{3}^{2−}$	+0.017
${[{AlF}_{6}]}^{3−} + 3 e^{-} ⟶ Al + 6 F^{-}$	−2.07
${Al}^{3+} + 3 e^{-} ⟶ Al$	−1.662
${Am}^{3+} + 3 e^{-} ⟶ Am$	−2.048
${Au}^{3+} + 3 e^{-} ⟶ Au$	+1.498
${Au}^{+} + e^{-} ⟶ Au$	+1.692
${Ba}^{2+} + 2 e^{-} ⟶ Ba$	−2.912
${Be}^{2+} + 2 e^{-} ⟶ Be$	−1.847
${Br}_{2} (a q) + 2 e^{-} ⟶ 2 {Br}^{-}$	+1.0873
${Ca}^{2+} + 2 e^{-} ⟶ Ca$	−2.868
${Ce}^{3} + 3 e^{-} ⟶ Ce$	−2.483
${Ce}^{4+} + e^{-} ⟶ {Ce}^{3+}$	+1.61
${Cd}^{2+} + 2 e^{-} ⟶ Cd$	−0.4030
${[Cd {(CN)}_{4}]}^{2−} + 2 e^{-} ⟶ Cd + 4 {CN}^{-}$	−1.09
${[Cd {({NH}_{3})}_{4}]}^{2+} + 2 e^{-} ⟶ Cd + 4 {NH}_{3}$	−0.61
$CdS + 2 e^{-} ⟶ Cd + S^{2−}$	−1.17
${Cl}_{2} + 2 e^{-} ⟶ 2 {Cl}^{-}$	+1.35827
${ClO}_{4}^{-} + H_{2} O + 2 e^{-} ⟶ {ClO}_{3}^{-} + 2 {OH}^{-}$	+0.36
${ClO}_{3}^{-} + H_{2} O + 2 e^{-} ⟶ {ClO}_{2}^{-} + 2 {OH}^{-}$	+0.33
${ClO}_{2}^{-} + H_{2} O + 2 e^{-} ⟶ {ClO}^{-} + 2 {OH}^{-}$	+0.66
${ClO}^{-} + H_{2} O + 2 e^{-} ⟶ {Cl}^{-} + 2 {OH}^{-}$	+0.89
${ClO}_{4}^{-} + 2 H_{3} O^{+} + 2 e^{-} ⟶ {ClO}_{3}^{-} + 3 H_{2} O$	+1.189
${ClO}_{3}^{-} + 3 H_{3} O^{+} + 2 e^{-} ⟶ {HClO}_{2} + 4 H_{2} O$	+1.21
$HClO + H_{3} O^{+} + 2 e^{-} ⟶ {Cl}^{-} + 2 H_{2} O$	+1.482
$HClO + H_{3} O^{+} + e^{-} ⟶ \frac{1}{2} {Cl}_{2} + 2 H_{2} O$	+1.611
${HClO}_{2} + 2 H_{3} O^{+} + 2 e^{-} ⟶ HClO + 3 H_{2} O$	+1.628
${Co}^{3+} + e^{-} ⟶ {Co}^{2+} (2 mol // H_{2} {SO}_{4})$	+1.83
${Co}^{2+} + 2 e^{-} ⟶ Co$	−0.28
${[Co {({NH}_{3})}_{6}]}^{3+} + e^{-} ⟶ {[Co {({NH}_{3})}_{6}]}^{2+}$	+0.1
$Co {(OH)}_{3} + e^{-} ⟶ Co {(OH)}_{2} + {OH}^{-}$	+0.17
${Cr}^{3} + 3 e^{-} ⟶ Cr$	−0.744
${Cr}^{3+} + e^{-} ⟶ {Cr}^{2+}$	−0.407
${Cr}^{2+} + 2 e^{-} ⟶ Cr$	−0.913
${[Cu {(CN)}_{2}]}^{-} + e^{-} ⟶ Cu + 2 {CN}^{-}$	−0.43
${CrO}_{4}^{2−} + 4 H_{2} O + 3 e^{-} ⟶ Cr {(OH)}_{3} + 5 {OH}^{-}$	−0.13
${Cr}_{2} O_{7}^{2−} + 14 H_{3} O^{+} + 6 e^{-} ⟶ 2 {Cr}^{3+} + 21 H_{2} O$	+1.232
${[Cr {(OH)}_{4}]}^{-} + 3 e^{-} ⟶ Cr + 4 {OH}^{-}$	−1.2
$Cr {(OH)}_{3} + 3 e^{-} ⟶ Cr + 3 {OH}^{-}$	−1.48
${Cu}^{2+} + e^{-} ⟶ {Cu}^{+}$	+0.153
${Cu}^{2+} + 2 e^{-} ⟶ Cu$	+0.337
${Cu}^{+} + e^{-} ⟶ Cu$	+0.521
$F_{2} + 2 e^{-} ⟶ 2 F^{-}$	+2.866
${Fe}^{2+} + 2 e^{-} ⟶ Fe$	−0.447
${Fe}^{3+} + e^{-} ⟶ {Fe}^{2+}$	+0.771
${[Fe {(CN)}_{6}]}^{3−} + e^{-} ⟶ {[Fe {(CN)}_{6}]}^{4−}$	+0.36
$Fe {(OH)}_{2} + 2 e^{-} ⟶ Fe + 2 {OH}^{-}$	−0.88
$FeS + 2 e^{-} ⟶ Fe + S^{2−}$	−1.01
${Ga}^{3+} + 3 e^{-} ⟶ Ga$	−0.549
${Gd}^{3+} + 3 e^{-} ⟶ Gd$	−2.279
$\frac{1}{2} H_{2} + e^{-} ⟶ H^{-}$	−2.23
$2 H_{2} O + 2 e^{-} ⟶ H_{2} + 2 {OH}^{-}$	−0.8277
$H_{2} O_{2} + 2 H_{3} O^{+} + 2 e^{-} ⟶ 4 H_{2} O$	+1.776
$2 H_{3} O^{+} + 2 e^{-} ⟶ H_{2} + 2 H_{2} O$	0.00
${HO}_{2}^{-} + H_{2} O + 2 e^{-} ⟶ 3 {OH}^{-}$	+0.878
${Hf}^{4+} + 4 e^{-} ⟶ Hf$	−1.55
${Hg}^{2+} + 2 e^{-} ⟶ Hg$	+0.851
$2 {Hg}^{2+} + 2 e^{-} ⟶ {Hg}_{2}^{2+}$	+0.92
${Hg}_{2}^{2+} + 2 e^{-} ⟶ 2 Hg$	+0.7973
${[{HgBr}_{4}]}^{2−} + 2 e^{-} ⟶ Hg + 4 {Br}^{-}$	+0.21
${Hg}_{2} {Cl}_{2} + 2 e^{-} ⟶ 2 Hg + 2 {Cl}^{-}$	+0.26808
${[Hg {(CN)}_{4}]}^{2−} + {2e}^{-} ⟶ Hg + {4CN}^{-}$	−0.37
${[{HgI}_{4}]}^{2−} + {2e}^{-} ⟶ Hg + {4I}^{-}$	−0.04
$HgS + {2e}^{-} ⟶ Hg + S^{2−}$	−0.70
$I_{2} + {2e}^{-} ⟶ {2I}^{-}$	+0.5355
${In}^{3+} + {3e}^{-} ⟶ In$	−0.3382
$K^{+} + e^{-} ⟶ K$	−2.931
${La}^{3+} + {3e}^{-} ⟶ La$	−2.52
${Li}^{+} + e^{-} ⟶ Li$	−3.04
${Lu}^{3+} + {3e}^{-} ⟶ Lu$	−2.28
${Mg}^{2+} + {2e}^{-} ⟶ Mg$	−2.372
${Mn}^{2+} + {2e}^{-} ⟶ Mn$	−1.185
${MnO}_{2} + {2H}_{2} O + {2e}^{-} ⟶ Mn {(OH)}_{2} + {2OH}^{-}$	−0.05
${MnO}_{4}^{-} + {2H}_{2} O + {3e}^{-} ⟶ {MnO}_{2} + {4OH}^{-}$	+0.558
${MnO}_{2} + 4 H^{+} + 2 e^{-} ⟶ {Mn}^{2+} + 2 H_{2} O$	+1.23
${MnO}_{4}^{-} + 8 H^{+} + 5 e^{-} ⟶ {Mn}^{2+} + 4 H_{2} O$	+1.507
${Na}^{+} + e^{-} ⟶ Na$	−2.71
${Nd}^{3+} + {3e}^{-} ⟶ Nd$	−2.323
${Ni}^{2+} + {2e}^{-} ⟶ Ni$	−0.257
${[Ni {({NH}_{3})}_{6}]}^{2+} + {2e}^{-} ⟶ Ni + {6NH}_{3}$	−0.49
${NiO}_{2} + 4 H^{+} + 2 e^{-} ⟶ {Ni}^{2+} + 2 H_{2} O$	+1.593
${NiO}_{2} + {2H}_{2} O + {2e}^{-} ⟶ Ni {(OH)}_{2} + {2OH}^{-}$	+0.49
$NiS + {2e}^{-} ⟶ Ni + S^{2−}$	+0.76
${NO}_{3}^{-} + 4 H^{+} + 3 e^{-} ⟶ NO + 2 H_{2} O$	+0.957
${NO}_{3}^{-} + 3 H^{+} + 2 e^{-} ⟶ {HNO}_{2} + H_{2} O$	+0.92
${NO}_{3}^{-} + H_{2} O + {2e}^{-} ⟶ {NO}_{2}^{-} + {2OH}^{-}$	+0.10
${Np}^{3+} + {3e}^{-} ⟶ Np$	−1.856
$O_{2} + {2H}_{2} O + {4e}^{-} ⟶ {4OH}^{-}$	+0.401
$O_{2} + 2 H^{+} + 2 e^{-} ⟶ H_{2} O_{2}$	+0.695
$O_{2} + 4 H^{+} + 4 e^{-} ⟶ 2 H_{2} O$	+1.229
${Pb}^{2+} + {2e}^{-} ⟶ Pb$	−0.1262
${PbO}_{2} + {SO}_{4}^{2−} + 4 H^{+} + 2 e^{-} ⟶ {PbSO}_{4} + 2 H_{2} O$	+1.69
$PbS + {2e}^{-} ⟶ Pb + S^{2−}$	−0.95
${PbSO}_{4} + {2e}^{-} ⟶ Pb + {SO}_{4}^{2−}$	−0.3505
${Pd}^{2+} + {2e}^{-} ⟶ Pd$	+0.987
${[{PdCl}_{4}]}^{2−} + {2e}^{-} ⟶ Pd + {4Cl}^{-}$	+0.591
${Pt}^{2+} + {2e}^{-} ⟶ Pt$	+1.20
${[{PtBr}_{4}]}^{2−} + {2e}^{-} ⟶ Pt + {4Br}^{-}$	+0.58
${[{PtCl}_{4}]}^{2−} + {2e}^{-} ⟶ Pt + {4Cl}^{-}$	+0.755
${[{PtCl}_{6}]}^{2−} + {2e}^{-} ⟶ {[{PtCl}_{4}]}^{2−} + {2Cl}^{-}$	+0.68
${Pu}^{3} + {3e}^{-} ⟶ Pu$	−2.03
${Ra}^{2+} + {2e}^{-} ⟶ Ra$	−2.92
${Rb}^{+} + e^{-} ⟶ Rb$	−2.98
${[{RhCl}_{6}]}^{3−} + {3e}^{-} ⟶ Rh + {6Cl}^{-}$	+0.44
$S + {2e}^{-} ⟶ S^{2−}$	−0.47627
$S + 2 H^{+} + 2 e^{-} ⟶ H_{2} S$	+0.142
${Sc}^{3+} + {3e}^{-} ⟶ Sc$	−2.09
$Se + 2 H^{+} + 2 e^{-} ⟶ H_{2} Se$	−0.399
${[{SiF}_{6}]}^{2−} + {4e}^{-} ⟶ Si + {6F}^{-}$	−1.2
${SiO}_{3}^{2−} + {3H}_{2} O + {4e}^{-} ⟶ Si + {6OH}^{-}$	−1.697
${SiO}_{2} + 4 H^{+} + 4 e^{-} ⟶ Si + 2 H_{2} O$	−0.86
${Sm}^{3+} + {3e}^{-} ⟶ Sm$	−2.304
${Sn}^{4+} + {2e}^{-} ⟶ {Sn}^{2+}$	+0.151
${Sn}^{2+} + {2e}^{-} ⟶ Sn$	−0.1375
${[{SnF}_{6}]}^{2−} + {4e}^{-} ⟶ Sn + {6F}^{-}$	−0.25
$SnS + {2e}^{-} ⟶ Sn + S^{2−}$	−0.94
${Sr}^{2+} + {2e}^{-} ⟶ Sr$	−2.89
${TeO}_{2} + 4 H^{+} + 4 e^{-} ⟶ Te + 2 H_{2} O$	+0.593
${Th}^{4+} + {4e}^{-} ⟶ Th$	−1.90
${Ti}^{2+} + {2e}^{-} ⟶ Ti$	−1.630
$U^{3+} + {3e}^{-} ⟶ U$	−1.79
$V^{2+} + {2e}^{-} ⟶ V$	−1.19
$Y^{3+} + {3e}^{-} ⟶ Y$	−2.37
${Zn}^{2+} + {2e}^{-} ⟶ Zn$	−0.7618
${[Zn {(CN)}_{4}]}^{2−} + {2e}^{-} ⟶ Zn + {4CN}^{-}$	−1.26
${[Zn {({NH}_{3})}_{4}]}^{2+} + {2e}^{-} ⟶ Zn + {4NH}_{3}$	−1.04
$Zn {(OH)}_{2} + {2e}^{-} ⟶ Zn + {2OH}^{-}$	−1.245
${[Zn {(OH)}_{4}]}^{2} + {2e}^{-} ⟶ Zn + {4OH}^{-}$	−1.199
$ZnS + {2e}^{-} ⟶ Zn + S^{2−}$	−1.40
${Zr}^{4} + {4e}^{-} ⟶ Zr$	−1.539

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