# Standard electrode potential (data page)

The data values of standard electrode potentials (E°) are given in the table below, in volts relative to the standard hydrogen electrode, and are for the following conditions:

• A temperature of 298.15 K (25.00 °C; 77.00 °F).
• An effective concentration of 1 mol/L for each aqueous species or a species in a mercury amalgam (an alloy of mercury with another metal).
• A partial pressure of 101.325 kPa (absolute) (1 atm, 1.01325 bar) for each gaseous reagent. This pressure is used because most literature data are still given for this value (1 atm) rather than for the current standard of 100 kPa (1 bar) presently considered in the standard state.
• An activity of unity for each pure solid, pure liquid, or for water (solvent). The relation in electrode potential of metals in saltwater (as electrolyte) is given in the galvanic series.
• Although many of the half cells are written for multiple-electron transfers, the tabulated potentials are for a single-electron transfer. All of the reactions should be divided by the stoichiometric coefficient for the electron to get the corresponding corrected reaction equation. For example, the equation Fe2+ + 2e ⇌ Fe(s) (–0.44 V) means that it requires 2 × 0.44 eV = 0.88 eV of energy to be absorbed (hence the minus sign) in order to create one neutral atom of Fe(s) from one Fe2+ ion and two electrons, or 0.44 eV per electron, which is 0.44 J/C of electrons, which is 0.44 V.
• After dividing by the number of electrons, the standard potential E° is related to the standard Gibbs free energy of formation ΔGf° by:
${\displaystyle E={\frac {\sum \Delta G_{\text{left}}-\sum \Delta G_{\text{right}}}{F}}}$
where F is the Faraday constant. For example, in the equation Fe2+ + 2e ⇌ Fe(s) (–0.44 V), the Gibbs energy required to create one neutral atom of Fe(s) from one Fe2+ ion and two electrons is 2 × 0.44 eV = 0.88 eV, or 84 895 J/mol of electrons, which is just the Gibbs energy of formation of an Fe2+ ion, since the energies of formation of e and Fe(s) are both zero.
The Nernst equation will then give potentials at concentrations, pressures, and temperatures other than standard.
• Note that the table may lack consistency due to data from different sources. For example:
 Cu+ +  e− ⇌ Cu(s) (E1 = +0.520 V) Cu2+ + 2 e− ⇌ Cu(s) (E2 = +0.337 V) Cu2+ +  e− ⇌ Cu+ (E3 = +0.159 V)
Calculating the potential using Gibbs free energy (E
3
= 2E
2
E
1
) gives the potential for E
3
as 0.154 V, not the experimental value of 0.159 V.

## Table of standard electrode potentials

Legend: (s) – solid; (l) – liquid; (g) – gas; (aq) – aqueous (default for all charged species); (Hg) – amalgam; bold – water electrolysis equations.

Element Half-reaction / V Electrons Ref.
Oxidant Reductant
Sr Sr+
+ e
Sr(s) -4.101 1 [1]
Ca Ca+
+ e
Ca(s) -3.8 1 [1]
Th Th4+
+ e
Th3+
-3.6 1 [2]
Pr Pr3+
+ e
Pr2+
-3.1 1 [1]
N 3N
2
(g) + 2H+ + 2e
2HN
3
(aq)
-3.09 2 [3][4]
Li Li+
+ e
Li(s) -3.0401 1 [4][5]
N N
2
(g) + 4H2O + 2e
2NH
2
OH
(aq) + 2OH
-3.04 2 [3]
Cs Cs+
+ e
Cs(s) -3.026 1 [4]
Ca Ca(OH)
2
+ 2e
Ca(s) + 2OH -3.02 2 [1]
Er Er3+
+ e
Er2+
-3 1 [1]
Ba Ba(OH)
2
+ 2e
Ba(s) + 2OH -2.99 2 [1]
Rb Rb+
+ e
Rb(s) -2.98 1 [4]
K K+
+ e
K(s) -2.931 1 [4]
Ba Ba2+
+ 2e
Ba(s) -2.912 2 [4]
La La(OH)
3
(s) + 3e
La(s) + 3OH -2.9 3 [4]
Fr Fr+
+ e
Fr(s) -2.9 1 [1]
Sr Sr2+
+ 2e
Sr(s) -2.899 2 [4]
Sr Sr(OH)
2
+ 2e
Sr(s) + 2OH -2.88 2 [1]
Ca Ca2+
+ 2e
Ca(s) -2.868 2 [4][5]
Li Li+
+ C
6
(s) + e
LiC
6
(s)
-2.84 1 [4]
Eu Eu2+
+ 2e
Eu(s) -2.812 2 [4]
Ra Ra2+
+ 2e
Ra(s) -2.8 2 [4]
Ho Ho3+
+ e
Ho2+ -2.8 1 [1]
Bk Bk3+
+ e
Bk2+
-2.8 1 [1]
Yb Yb2+
+ 2e
Yb(s) -2.76 2 [1]
Na Na+
+ e
Na(s) -2.71 1 [4][6]
Mg Mg+
+ e
Mg(s) -2.7 1 [1]
Nd Nd3+
+ e
Nd2+
-2.7 1 [1]
Mg Mg(OH)
2
+ 2e
Mg(s) + 2OH -2.69 2 [1]
Sm Sm2+
+ 2e
Sm(s) -2.68 2 [1]
Be Be
2
O2−
3
+ 3H2O + 4e
2Be(s) + 6OH -2.63 4 [1]
Pm Pm3+
+ e
Pm2+
-2.6 1 [1]
Dy Dy3+
+ e
Dy2+
-2.6 1 [1]
No No2+
+ 2e
No -2.5 2 [1]
Hf HfO(OH)
2
+ H2O + 4e
Hf(s) + 4OH -2.5 4 [1]
Th Th(OH)
4
+ 4e
Th(s) + 4OH -2.48 4 [1]
Md Md2+
+ 2e
Md -2.4 2 [1]
Tm Tm2+
+ 2e
Tm(s) -2.4 2 [1]
La La3+
+ 3e
La(s) -2.379 3 [4]
Y Y3+
+ 3e
Y(s) -2.372 3 [4]
Mg Mg2+
+ 2e
Mg(s) -2.372 2 [4]
Zr ZrO(OH)
2
(s) + H2O + 4e
Zr(s) + 4OH -2.36 4 [4]
Pr Pr3+
+ 3e
Pr(s) -2.353 3 [1]
Ce Ce3+
+ 3e
Ce(s) -2.336 3 [1]
Er Er3+
+ 3e
Er(s) -2.331 3 [1]
Ho Ho3+
+ 3e
Ho(s) -2.33 3 [1]
Al H
2
AlO
3
+ H2O + 3e
Al(s) + 4OH -2.33 3 [1]
Nd Nd3+
+ 3e
Nd(s) -2.323 3 [1]
Tm Tm3+
+ 3e
Tm(s) -2.319 3 [1]
Al Al(OH)
3
(s) + 3e
Al(s) + 3OH -2.31 3
Sm Sm3+
+ 3e
Sm(s) -2.304 3 [1]
Fm Fm2+ + 2e Fm -2.3 2 [1]
Am Am3+
+ e
Am2+
-2.3 1 [1]
Dy Dy3+
+ 3e
Dy(s) -2.295 3 [1]
Lu Lu3+
+ 3e
Lu(s) -2.28 3 [1]
Tb Tb3+
+ 3e
Tb(s) -2.28 3 [1]
Gd Gd3+
+ 3e
Gd(s) -2.279 3 [1]
H H
2
(g) + 2e
2H
-2.23 2 [1]
Es Es2+
+ 2e
Es(s) -2.23 2 [1]
Pm Pm2+
+ 2e
Pm(s) -2.2 2 [1]
Tm Tm3+
+ e
Tm2+ -2.2 1 [1]
Dy Dy2+
+ 2e
Dy(s) -2.2 2 [1]
Ac Ac3+
+ 3e
Ac(s) -2.2 3 [1]
Yb Yb3+
+ 3e
Yb(s) -2.19 3 [1]
Cf Cf2+
+ 2e
Cf(s) -2.12 2 [1]
Nd Nd2+
+ 2e
Nd(s) -2.1 2 [1]
Ho Ho2+
+ 2e
Ho(s) -2.1 2 [1]
Sc Sc3+
+ 3e
Sc(s) -2.077 3 [7]
Al AlF3−
6
+ 3e
Al(s) + 6F
-2.069 3 [1]
Am Am3+
+ 3e
Am(s) -2.048 3 [1]
Cm Cm3+
+ 3e
Cm(s) -2.04 3 [1]
Pu Pu3+
+ 3e
Pu(s) -2.031 3 [1]
Pr Pr2+
+ 2e
Pr(s) -2 2 [1]
Er Er2+
+ 2e
Er(s) -2 2 [1]
Eu Eu3+
+ 3e
Eu(s) -1.991 3 [1]
Lr Lr3+
+ 3e
Lr -1.96 3 [1]
Cf Cf3+
+ 3e
Cf(s) -1.94 3 [1]
Es Es3+
+ 3e
Es(s) -1.91 3 [1]
Pa Pa4+
+ e
Pa3+
-1.9 1 [1]
Am Am2+
+ 2e
Am(s) -1.9 2 [1]
Th Th4+
+ 4e
Th(s) -1.899 4 [1]
Fm Fm3+
+ 3e
Fm -1.89 3 [1]
Np Np3+
+ 3e
Np(s) -1.856 3 [1]
Be Be2+
+ 2e
Be(s) -1.847 2 [1]
P H
2
PO
2
+ e
P(s) + 2OH -1.82 1 [1]
U U3+
+ 3e
U(s) -1.798 3 [1]
Sr Sr2+
+ 2e
Sr(Hg) -1.793 2 [1]
B H
2
BO
3
+ H2O + 3e
B(s) + 4OH -1.79 3 [1]
Th ThO
2
+ 4H+ + 4e
Th(s) + 2H2O -1.789 4 [1]
Hf HfO2+
+ 2H+ + 4e
Hf(s) + H2O -1.724 4 [1]
P HPO2−
3
+ 2H2O + 3e
P(s) + 5OH -1.71 3 [1]
Si SiO2−
3
+ 3H2O + 4e
Si(s) + 6OH -1.697 4 [1]
Al Al3+
+ 3e
Al(s) -1.662 3 [1]
Ti Ti2+
+ 2e
Ti(s) -1.63 2 [6]
Zr ZrO
2
(s) + 4H+ + 4e
Zr(s) + 2H2O -1.553 4 [8]
Zr Zr4+
+ 4e
Zr(s) -1.45 4 [8]
Ti Ti3+
+ 3e
Ti(s) -1.37 3 [9]
Ti TiO(s) + 2H+ + 2e Ti(s) + H2O -1.31 2
Ti Ti
2
O
3
(s) + 2H+ + 2e
2TiO(s) + H2O -1.23 2
Zn Zn(OH)2−
4
+ 2e
Zn(s) + 4OH -1.199 2 [8]
Mn Mn2+
+ 2e
Mn(s) -1.185 2 [8]
Fe Fe(CN)4−
6
+ 6H+ + 2e
Fe(s) + 6HCN(aq) -1.16 2 [10]
Te Te(s) + 2e Te2−
-1.143 2 [11]
V V2+
+ 2e
V(s) -1.13 2 [11]
Nb Nb3+
+ 3e
Nb(s) -1.099 3
Sn Sn(s) + 4H+ + 4e SnH
4
(g)
-1.07 4
Ti TiO2+
+ 2H+ + 4e
Ti(s) + H2O -0.93 4
Si SiO
2
(s) + 4H+ + 4e
Si(s) + 2H2O -0.91 4
B B(OH)
3
(aq) + 3H+ + 3e
B(s) + 3H2O -0.89 3
Fe Fe(OH)
2
(s) + 2e
Fe(s) + 2OH -0.89 2 [10]
Fe Fe
2
O
3
(s) + 3H2O + 2e
2Fe(OH)
2
(s) + 2OH
-0.86 2 [10]
H 2H2O + 2e H
2
(g) + 2OH
-0.8277 2 [8]
Bi Bi(s) + 3H+ + 3e BiH
3
-0.8 3 [8]
Zn Zn2+
+ 2e
Zn(Hg) -0.7628 2 [8]
Zn Zn2+
+ 2e
Zn(s) -0.7618 2 [8]
Ta Ta
2
O
5
(s) + 10H+ + 10e
2Ta(s) + 5H2O -0.75 10
Cr Cr3+
+ 3e
Cr(s) -0.74 3
Ni Ni(OH)
2
(s) + 2e
Ni(s) + 2OH -0.72 2 [1]
Ag Ag
2
S
(s) + 2e
2Ag(s) + S2−
(aq)
-0.69 2
Au [Au(CN)
2
]
+ e
Au(s) + 2CN
-0.6 1
Ta Ta3+
+ 3e
Ta(s) -0.6 3
Pb PbO(s) + H2O + 2e Pb(s) + 2OH -0.58 2
Ti 2TiO
2
(s) + 2H+ + 2e
Ti
2
O
3
(s) + H2O
-0.56 2
Ga Ga3+
+ 3e
Ga(s) -0.53 3
U U4+
+ e
U3+
-0.52 1 [12]
P H
3
PO
2
(aq) + H+ + e
P(white)[note 1] + 2H2O -0.508 1 [8]
P H
3
PO
3
(aq) + 2H+ + 2e
H
3
PO
2
(aq) + H2O
-0.499 2 [8]
Ni NiO
2
(s) + 2H2O + 2e
Ni(OH)
2
(s) + 2OH
-0.49 2 [1]
P H
3
PO
3
(aq) + 3H+ + 3e
P(red)[note 1] + 3H2O -0.454 3 [8]
Cu Cu(CN)
2
+ e
Cu(s) + 2CN
-0.44 1 [11]
Fe Fe2+
+ 2e
Fe(s) -0.44 2 [6]
C 2CO
2
(g) + 2H+ + 2e
HOOCCOOH(aq) -0.43 2
Cr Cr3+
+ e
Cr2+
-0.42 1
Cd Cd2+
+ 2e
Cd(s) -0.4 2 [6]
Ge GeO
2
(s) + 2H+ + 2e
GeO(s) + H2O -0.37 2
Cu Cu
2
O
(s) + H2O + 2e
2Cu(s) + 2OH -0.36 2 [8]
Pb PbSO
4
(s) + 2e
Pb(s) + SO2−
4
-0.3588 2 [8]
Pb PbSO
4
(s) + 2e
Pb(Hg) + SO2−
4
-0.3505 2 [8]
Eu Eu3+
+ e
Eu2+
-0.35 1 [12]
In In3+
+ 3e
In(s) -0.34 3 [11]
Tl Tl+
+ e
Tl(s) -0.34 1 [11]
Ge Ge(s) + 4H+ + 4e GeH
4
(g)
-0.29 4
Co Co2+
+ 2e
Co(s) -0.28 2 [8]
P H
3
PO
4
(aq) + 2H+ + 2e
H
3
PO
3
(aq) + H2O
-0.276 2 [8]
V V3+
+ e
V2+
-0.26 1 [6]
Ni Ni2+
+ 2e
Ni(s) -0.25 2
As As(s) + 3H+ + 3e AsH
3
(g)
-0.23 3 [11]
Ag AgI(s) + e Ag(s) + I
-0.15224 1 [8]
Mo MoO
2
(s) + 4H+ + 4e
Mo(s) + 2H2O -0.15 4
Si Si(s) + 4H+ + 4e SiH
4
(g)
-0.14 4
Sn Sn2+
+ 2e
Sn(s) -0.13 2
O O
2
(g) + H+ + e
HO
2
(aq)
-0.13 1
Pb Pb2+
+ 2e
Pb(s) -0.126 2 [6]
W WO
2
(s) + 4H+ + 4e
W(s) + 2H2O -0.12 4
P P(red) + 3H+ + 3e PH
3
(g)
-0.111 3 [8]
C CO
2
(g) + 2H+ + 2e
HCOOH(aq) -0.11 2
Se Se(s) + 2H+ + 2e H
2
Se
(g)
-0.11 2
C CO
2
(g) + 2H+ + 2e
CO(g) + H2O -0.11 2
Cu Cu(NH
3
)+
2
+ e
Cu(s) + 2NH
3
(aq)
-0.1 1 [11]
Sn SnO(s) + 2H+ + 2e Sn(s) + H2O -0.1 2
Sn SnO
2
(s) + 2H+ + 2e
SnO(s) + H2O -0.09 2
W WO
3
(aq) + 6H+ + 6e
W(s) + 3H2O -0.09 6 [11]
Fe Fe
3
O
4
(s) + 8H+ + 8e
3Fe(s) + 4H2O -0.085 8 [13]
P P(white) + 3H+ + 3e PH
3
(g)
-0.063 3 [8]
Fe Fe3+
+ 3e
Fe(s) -0.04 3 [10]
C HCOOH(aq) + 2H+ + 2e HCHO(aq) + H2O -0.03 2
H 2H+ + 2e H
2
(g)
0 2
Ag AgBr(s) + e Ag(s) + Br
0.07133 1 [8]
S S
4
O2−
6
+ 2e
2S
2
O2−
3
0.08 2
N N
2
(g) + 2H2O + 6H+ + 6e
2NH
4
OH
(aq)
0.092 6
Hg HgO(s) + H2O + 2e Hg(l) + 2OH 0.0977 2
Cu Cu(NH
3
)2+
4
+ e
Cu(NH
3
)+
2
+ 2NH
3
(aq)
0.1 1 [11]
Ru Ru(NH
3
)3+
6
+ e
Ru(NH
3
)2+
6
0.1 1 [12]
N N
2
H
4
(aq) + 4H2O + 2e
2NH+
4
+ 4OH
0.11 2 [3]
Mo H
2
MoO
4
(aq) + 6H+ + 6e
Mo(s) + 4H2O 0.11 6
Ge Ge4+
+ 4e
Ge(s) 0.12 4
C C(s) + 4H+ + 4e CH
4
(g)
0.13 4 [11]
C HCHO(aq) + 2H+ + 2e CH
3
OH
(aq)
0.13 2
S S(s) + 2H+ + 2e H
2
S
(g)
0.14 2
Sn Sn4+
+ 2e
Sn2+
0.15 2
Cu Cu2+
+ e
Cu+
0.159 1 [11]
S HSO
4
+ 3H+ + 2e
SO
2
(aq) + 2H2O
0.16 2
U UO2+
2
+ e
UO+
2
0.163 1 [12]
S SO2−
4
+ 4H+ + 2e
SO
2
(aq) + 2H2O
0.17 2
Ti TiO2+
+ 2H+ + e
Ti3+
+ H2O
0.19 1
Sb SbO+
+ 2H+ + 3e
Sb(s) + H2O 0.2 3
Fe 3Fe
2
O
3
(s) + 2H+ + 2e
2Fe
3
O
4
(s) + H2O
0.22 2 [14]: p.100
Ag AgCl(s) + e Ag(s) + Cl
0.22233 1 [8]
As H
3
AsO
3
(aq) + 3H+ + 3e
As(s) + 3H2O 0.24 3
Ru Ru3+
(aq) + e
Ru2+
(aq)
0.249 1 [15]
Ge GeO(s) + 2H+ + 2e Ge(s) + H2O 0.26 2
U UO+
2
+ 4H+ + e
U4+
+ 2H2O
0.273 1 [12]
Re Re3+
+ 3e
Re(s) 0.3 3
At At + e At- 0.3 1 [16]
Bi Bi3+
+ 3e
Bi(s) 0.308 3 [8]
Cu Cu2+
+ 2e
Cu(s) 0.337 2 [11]
V [VO]2+
+ 2H+ + e
V3+
+ H2O
0.34 1
Fe [Fe(CN)
6
]3−
+ e
[Fe(CN)
6
]4−
0.3704 1 [17]
Fe Fc+
+ e
Fc(s) 0.4 1 [18]
O O
2
(g) + 2H2O + 4e
4OH(aq) 0.401 4 [6]
Mo H
2
MoO
4
+ 6H+ + 3e
Mo3+
+ 4H2O
0.43 3
Ru Ru2+
(aq) + 2e
Ru 0.455 2 [15]
C CH
3
OH
(aq) + 2H+ + 2e
CH
4
(g) + H2O
0.5 2
S SO
2
(aq) + 4H+ + 4e
S(s) + 2H2O 0.5 4
Cu Cu+
+ e
Cu(s) 0.52 1 [11]
C CO(g) + 2H+ + 2e C(s) + H2O 0.52 2
I I
3
+ 2e
3I
0.53 2 [6]
I I
2
(s) + 2e
2I
0.54 2 [6]
Au [AuI
4
]
+ 3e
Au(s) + 4I
0.56 3
As H
3
AsO
4
(aq) + 2H+ + 2e
H
3
AsO
3
(aq) + H2O
0.56 2
Au [AuI
2
]
+ e
Au(s) + 2I
0.58 1
Mn MnO
4
+ 2H2O + 3e
MnO
2
(s) + 4OH
0.595 3 [1]
S S
2
O2−
3
+ 6H+ + 4e
2S(s) + 3H2O 0.6 4
Mo H
2
MoO
4
(aq) + 2H+ + 2e
MoO
2
(s) + 2H2O
0.65 2
C + 2H+ + 2e 0.6992 2 [8]
O O
2
(g) + 2H+ + 2e
H
2
O
2
(aq)
0.7 2
Tl Tl3+
+ 3e
Tl(s) 0.72 3
Pt PtCl2−
6
+ 2e
PtCl2−
4
+ 2Cl
0.726 2 [12]
Fe Fe
2
O
3
(s) + 6H+ + 2e
2Fe2+
+ 3H2O
0.728 2 [14]: p.100
Se H
2
SeO
3
(aq) + 4H+ + 4e
Se(s) + 3H2O 0.74 4
Pt PtCl2−
4
+ 2e
Pt(s) + 4Cl
0.758 2 [12]
Fe Fe3+
+ e
Fe2+
0.77 1
Ag Ag+
+ e
Ag(s) 0.7996 1 [8]
Hg Hg2+
2
+ 2e
2Hg(l) 0.8 2
N NO
3
(aq) + 2H+ + e
NO
2
(g) + H2O
0.8 1
Fe 2FeO2−
4
+ 5H2O + 6e
Fe
2
O
3
(s) + 10OH
0.81 6 [10]
Au [AuBr
4
]
+ 3e
Au(s) + 4Br
0.85 3
Hg Hg2+
+ 2e
Hg(l) 0.85 2
Ir [IrCl
6
]2−
+ e
[IrCl
6
]3−
0.87 1 [5]
Mn MnO
4
+ H+ + e
HMnO
4
0.9 1
Hg 2Hg2+
+ 2e
Hg2+
2
0.91 2 [11]
Pd Pd2+
+ 2e
Pd(s) 0.915 2 [12]
Au [AuCl
4
]
+ 3e
Au(s) + 4Cl
0.93 3
Mn MnO
2
(s) + 4H+ + e
Mn3+
+ 2H2O
0.95 1
N NO
3
(aq) + 4H+ + 3e
NO(g) + 2H2O(l) 0.958 3 [6]
Au [AuBr
2
]
+ e
Au(s) + 2Br
0.96 1
Fe Fe
3
O
4
(s) + 8H+ + 2e
3Fe2+
+ 4H2O
0.98 2 [14]: p.100
Xe [HXeO
6
]3−
+ 2H2O + 2e
[HXeO
4
]
+ 4OH
0.99 2 [19]
At HAtO + H+ + e At + H2O 1.0 1 [16]
V [VO
2
]+
(aq) + 2H+ + e
[VO]2+
(aq) + H2O
1 1 [20]
Te H
6
TeO
6
(aq) + 2H+ + 2e
TeO
2
(s) + 4H2O
1.02 2 [20]
Br Br
2
(l) + 2e
2Br
1.066 2 [8]
Br Br
2
(aq) + 2e
2Br
1.0873 2 [8]
Ru RuO
2
+ 4H+ + 2e
Ru2+
(aq) + 2H2O
1.120 2 [15]
Cu Cu2+
+ 2CN
+ e
Cu(CN)
2
1.12 1 [11]
I IO
3
+ 5H+ + 4e
HIO(aq) + 2H2O 1.13 4
Au [AuCl
2
]
+ e
Au(s) + 2Cl
1.15 1
Se HSeO
4
+ 3H+ + 2e
H
2
SeO
3
(aq) + H2O
1.15 2
Ag Ag
2
O
(s) + 2H+ + 2e
2Ag(s) + H2O 1.17 2
Cl ClO
3
+ 2H+ + e
ClO
2
(g) + H2O
1.18 1
Xe [HXeO
6
]3−
+ 5H2O + 8e
Xe(g) + 11OH 1.18 8 [19]
Pt Pt2+
+ 2e
Pt(s) 1.188 2 [12]
Cl ClO
2
(g) + H+ + e
HClO
2
(aq)
1.19 1
I 2IO
3
+ 12H+ + 10e
I
2
(s) + 6H2O
1.2 10
Mn MnO
2
(s) + 4H+ + 2e
Mn2+
+ 2H2O
1.224 2 [8]
O O
2
(g) + 4H+ + 4e
2H2O 1.229 4 [6]
Cl ClO
4
+ 2H+ + 2e
ClO
3
+ H2O
1.23 2 [21]
Ru [Ru(bipy)
3
]3+
+ e
[Ru(bipy)
3
]2+
1.24 1 [1]
Xe [HXeO
4
]
+ 3H2O + 6e
Xe(g) + 7OH 1.24 6 [19]
Tl Tl3+
+ 2e
Tl+
1.25 2
Cr Cr
2
O2−
7
+ 14H+ + 6e
2Cr3+
+ 7H2O
1.33 6
Cl Cl
2
(g) + 2e
2Cl
1.36 2 [6]
Ru RuO
4
(aq) + 8H+ + 5e
Ru2+
(aq) + 4H2O
1.368 5 [15]
Ru RuO
4
+ 4H+ + 4e
RuO
2
+ 2H2O
1.387 4 [15]
Co CoO
2
(s) + 4H+ + e
Co3+
+ 2H2O
1.42 1
N 2NH
3
OH+
+ H+ + 2e
N
2
H+
5
+ 2H2O
1.42 2 [3]
I 2HIO(aq) + 2H+ + 2e I
2
(s) + 2H2O
1.44 2
Br BrO
3
+ 5H+ + 4e
HBrO(aq) + 2H2O 1.45 4
Pb β-PbO
2
(s) + 4H+ + 2e
Pb2+
+ 2H2O
1.46 2 [11]
Pb α-PbO
2
(s) + 4H+ + 2e
Pb2+
+ 2H2O
1.468 2 [11]
Br 2BrO
3
+ 12H+ + 10e
Br
2
(l) + 6H2O
1.48 10
Cl 2ClO
3
+ 12H+ + 10e
Cl
2
(g) + 6H2O
1.49 10
Cl HClO(aq) + H+ + 2e Cl
(aq) + H2O
1.49 2 [1]
At HAtO3 + 4H+ + 4e HAtO + 2H2O 1.5 4 [16]
Mn MnO
4
+ 8H+ + 5e
Mn2+
+ 4H2O
1.51 5
O HO
2
+ H+ + e
H
2
O
2
(aq)
1.51 1
Au Au3+
+ 3e
Au(s) 1.52 3
Ru RuO2−
4
(aq) + 8H+ + 4e
Ru2+
(aq) + 4H2O
1.563 4 [15]
Ni NiO
2
(s) + 2H+ + 2e
Ni2+
+ 2OH
1.59 2
Ce Ce4+
+ e
Ce3+
1.61 1
Cl 2HClO(aq) + 2H+ + 2e Cl
2
(g) + 2H2O
1.63 2
I IO
4
+ 2H+ + 2e
IO
3
+ H2O
1.64 2 [21]
Ag Ag
2
O
3
(s) + 6H+ + 4e
2Ag+
+ 3H2O
1.67 4
Cl HClO
2
(aq) + 2H+ + 2e
HClO(aq) + H2O 1.67 2
Pb Pb4+
+ 2e
Pb2+
1.69 2 [11]
Mn MnO
4
+ 4H+ + 3e
MnO
2
(s) + 2H2O
1.7 3
Br BrO
4
+ 2H+ + 2e
BrO
3
+ H2O
1.74 2 [21]
Ag AgO(s) + 2H+ + e Ag+
+ H2O
1.77 1
O H
2
O
2
(aq) + 2H+ + 2e
2H2O 1.78 2
Co Co3+
+ e
Co2+
1.82 1
Au Au+
+ e
Au(s) 1.83 1 [11]
Ag Ag2+
+ e
Ag+
1.98 1 [11]
O S
2
O2−
8
+ 2e
2SO2−
4
2.01 2 [8]
O O
3
(g) + 2H+ + 2e
O
2
(g) + H2O
2.075 2 [12]
Mn HMnO
4
+ 3H+ + 2e
MnO
2
(s) + 2H2O
2.09 2
Xe XeO
3
(aq) + 6H+ + 6e
Xe(g) + 3H2O 2.12 6 [19]
Xe H
4
XeO
6
(aq) + 8H+ + 8e
Xe(g) + 6H2O 2.18 8 [19]
Fe FeO2−
4
+ 8H+ + 3e
Fe3+
+ 4H2O
2.2 3 [22]
Xe XeF
2
(aq) + 2H+ + 2e
Xe(g) + 2HF(aq) 2.32 2 [19]
Xe H
4
XeO
6
(aq) + 2H+ + 2e
XeO
3
(aq) + 3H2O
2.42 2 [19]
F F
2
(g) + 2e
2F
2.87 2 [5][6][11]
F F
2
(g) + 2H+ + 2e
2HF(aq) 3.05 2 [11]
Tb Tb4+ + e Tb3+ 3.1 1
Pr Pr4+ + e Pr3+ 3.2 1 [23]
Kr KrF
2
(aq) + 2e
Kr(g) + 2F
(aq)
3.27 2 [24]

## Notes

1. ^ a b Not specified in the indicated reference, but assumed due to the difference between the value −0.454 and that computed by (2×(−0.499) + (−0.508))/3 = −0.502, exactly matching the difference between the values for white (−0.063) and red (−0.111) phosphorus in equilibrium with PH3.

## References

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4. Vanýsek, Petr (2011). "Electrochemical Series". In Haynes, William M. (ed.). CRC Handbook of Chemistry and Physics (92nd ed.). CRC Press. pp. 5–80–9. ISBN 978-1-4398-5512-6.
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15. Greenwood and Earnshaw, p. 1077
16. ^ a b c Lavrukhina, Avgusta Konstantinovna; Pozdni︠a︡kov, Aleksandr Aleksandrovich (1970). Analytical chemistry of technetium, promethium, astatine and francium. Ann Arbor: Ann Arbor-Humphrey Science Publishers. p. 237. ISBN 0-250-39923-7. OCLC 186926.
17. ^ Rock, Peter A. (February 1966). "The Standard Oxidation Potential of the Ferrocyanide-Ferricyanide Electrode at 25° and the Entropy of Ferrocyanide Ion". The Journal of Physical Chemistry. 70 (2): 576–580. doi:10.1021/j100874a042. ISSN 0022-3654.
18. ^ Connelly, Neil G.; Geiger, William E. (1 January 1996). "Chemical Redox Agents for Organometallic Chemistry". Chemical Reviews. 96 (2): 877–910. doi:10.1021/cr940053x. PMID 11848774.
19. "compounds information". Xenon. WebElements Periodic Table of the Elements.
20. ^ a b Cotton, F. Albert; Wilkinson, Geoffrey; Murillo, Carlos A.; Bochmann, Manfred (1999), Advanced Inorganic Chemistry (6th ed.), New York: Wiley-Interscience, ISBN 0-471-19957-5.
21. ^ a b c Appelman, Evan H. (1973-04-01). "Nonexistent compounds. Two case histories". Accounts of Chemical Research. American Chemical Society (ACS). 6 (4): 113–117. doi:10.1021/ar50064a001. ISSN 0001-4842.
22. ^ Courtney, Arlene. "Oxidation Reduction Chemistry of the Elements". Ch 412 Advanced Inorganic Chemistry: Reading Materials. Western Oregon University.
23. ^ Petr Vanysek. "Electrochemical series" (PDF). depa.fquim.unam.mx. Archived (PDF) from the original on 2022-10-09.
24. ^ Leszczyński, P.J.; Grochala, W. (2013). "Strong Cationic Oxidizers: Thermal Decomposition, Electronic Structure and Magnetism of Their Compounds" (PDF). Acta Chim. Slov. 60 (3): 455–470. PMID 24169699. Archived (PDF) from the original on 2022-10-09.