Standard electrode potential (data page)

The data below tabulates standard electrode potentials (E°), in volts relative to the standard hydrogen electrode, at:

Temperature 298.15 K (25.00 °C; 77.00 °F);
Effective concentration 1 mol/L for each aqueous or amalgamated (mercury-alloyed) species;
Unit activity for each solvent and pure solid or liquid species; and
Absolute partial pressure 101.325 kPa (1.00000 atm; 1.01325 bar) for each gaseous reagent — the convention in most literature data but not the current standard state (100 kPa).

The Nernst equation adjusts for general concentrations, pressures, or temperatures.

Simultaneous half-reactions do not in general add voltages, but instead add Gibbs free energy change: the product of the voltage and the number of electrons transferred, typically the Faraday constant. For example, from Fe²⁺ + 2 e⁻ ⇌ Fe(s) (–0.44 V), the energy 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 e⁻). That value is also the standard formation energy for an Fe²⁺ ion, since e⁻ and Fe(s) both have zero formation energy.

Data from different sources may cause table inconsistencies. For example:

{\begin{alignedat}{4}&{\ce {Cu+ + e-}}&{}\rightleftharpoons {}&{\ce {Cu}}(s)&\quad \quad E_{1}=+0.520{\text{ V}}\\&{\ce {Cu^2+ + 2e-}}&{}\rightleftharpoons {}&{\ce {Cu}}&\quad \quad E_{2}=+0.337{\text{ V}}\\&{\ce {Cu^2+ + e-}}&{}\rightleftharpoons {}&{\ce {Cu+}}&\quad \quad E_{3}=+0.159{\text{ V}}\end{alignedat}}

Additivity of Gibbs energy implies

E_{3}={\frac {2\cdot E_{2}-1\cdot E_{1}}{1}}=0.154{\text{ V,}}

not the experimental 0.159 V.

Table of standard electrode potentials[edit]

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

Element	Half-reaction			E° / V	Electrons	Ref.
Element	Oxidant	⇌	Reductant	E° / V	Electrons	Ref.
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	Estimated^[3]
N	3N ₂(g) + 2 H⁺ + 2 e⁻	⇌	2HN ₃(aq)	-3.09	2	^[4]^[5]
Li	Li⁺ + e⁻	⇌	Li(s)	-3.0401	1	^[5]^[6]^: 153
N	N ₂(g) + 4H₂O + 2 e⁻	⇌	2NH ₂OH(aq) + 2 OH⁻	-3.04	2	^[4]
Cs	Cs⁺ + e⁻	⇌	Cs(s)	-3.026	1	^[5]
Ca	Ca(OH) ₂ + 2 e⁻	⇌	Ca(s) + 2 OH⁻	-3.02	2	^[1]
Er	Er³⁺ + e⁻	⇌	Er²⁺	-3	1	^[1]
Ba	Ba(OH) ₂ + 2 e⁻	⇌	Ba(s) + 2 OH⁻	-2.99	2	^[1]
Rb	Rb⁺ + e⁻	⇌	Rb(s)	-2.98	1	^[5]
K	K⁺ + e⁻	⇌	K(s)	-2.931	1	^[5]
Ba	Ba²⁺ + 2 e⁻	⇌	Ba(s)	-2.912	2	^[5]
La	La(OH) ₃(s) + 3 e⁻	⇌	La(s) + 3 OH⁻	-2.9	3	^[5]
Fr	Fr⁺ + e⁻	⇌	Fr(s)	-2.9	1	^[1]
Sr	Sr²⁺ + 2 e⁻	⇌	Sr(s)	-2.899	2	^[5]
Sr	Sr(OH) ₂ + 2 e⁻	⇌	Sr(s) + 2 OH⁻	-2.88	2	^[1]
Ca	Ca²⁺ + 2 e⁻	⇌	Ca(s)	-2.868	2	^[5]^[6]^: 153
Li	Li⁺ + C ₆(s) + e⁻	⇌	LiC ₆(s)	-2.84	1	^[5]
Eu	Eu²⁺ + 2 e⁻	⇌	Eu(s)	-2.812	2	^[5]
Ra	Ra²⁺ + 2 e⁻	⇌	Ra(s)	-2.8	2	^[5]
Ho	Ho³⁺ + e⁻	⇌	Ho²⁺	-2.8	1	^[1]
Bk	Bk³⁺ + e⁻	⇌	Bk²⁺	-2.8	1	^[1]
Yb	Yb²⁺ + 2 e⁻	⇌	Yb(s)	-2.76	2	^[1]
Na	Na⁺ + e⁻	⇌	Na(s)	-2.71	1	^[5]^[7]
Mg	Mg⁺ + e⁻	⇌	Mg(s)	-2.7	1	^[1]
Nd	Nd³⁺ + e⁻	⇌	Nd²⁺	-2.7	1	^[1]
Mg	Mg(OH) ₂ + 2 e⁻	⇌	Mg(s) + 2 OH⁻	-2.69	2	^[1]
Sm	Sm²⁺ + 2 e⁻	⇌	Sm(s)	-2.68	2	^[1]
Be	Be ₂O²⁻ ₃ + 3H₂O + 4 e⁻	⇌	2Be(s) + 6 OH⁻	-2.63	4	^[1]
Pm	Pm³⁺ + e⁻	⇌	Pm²⁺	-2.6	1	^[1]
Dy	Dy³⁺ + e⁻	⇌	Dy²⁺	-2.6	1	^[1]
No	No²⁺ + 2 e⁻	⇌	No	-2.5	2	^[1]
Hf	HfO(OH) ₂ + H₂O + 4 e⁻	⇌	Hf(s) + 4 OH⁻	-2.5	4	^[1]
Th	Th(OH) ₄ + 4 e⁻	⇌	Th(s) + 4 OH⁻	-2.48	4	^[1]
Md	Md²⁺ + 2 e⁻	⇌	Md	-2.4	2	^[1]
Tm	Tm²⁺ + 2 e⁻	⇌	Tm(s)	-2.4	2	^[1]
La	La³⁺ + 3 e⁻	⇌	La(s)	-2.379	3	^[5]
Y	Y³⁺ + 3 e⁻	⇌	Y(s)	-2.372	3	^[5]
Mg	Mg²⁺ + 2 e⁻	⇌	Mg(s)	-2.372	2	^[5]
Sc	ScF₃(aq) + 3 H⁺ + 3 e⁻	⇌	Sc(s) + 3HF(aq)	-2.37	3	^[6]^: 792
Zr	ZrO(OH) ₂(s) + H₂O + 4 e⁻	⇌	Zr(s) + 4 OH⁻	-2.36	4	^[5]
Pr	Pr³⁺ + 3 e⁻	⇌	Pr(s)	-2.353	3	^[1]
Ce	Ce³⁺ + 3 e⁻	⇌	Ce(s)	-2.336	3	^[1]
Er	Er³⁺ + 3 e⁻	⇌	Er(s)	-2.331	3	^[1]
Ho	Ho³⁺ + 3 e⁻	⇌	Ho(s)	-2.33	3	^[1]
Al	H ₂AlO⁻ ₃ + H₂O + 3 e⁻	⇌	Al(s) + 4 OH⁻	-2.33	3	^[1]
Nd	Nd³⁺ + 3 e⁻	⇌	Nd(s)	-2.323	3	^[1]
Tm	Tm³⁺ + 3 e⁻	⇌	Tm(s)	-2.319	3	^[1]
Al	Al(OH) ₃(s) + 3 e⁻	⇌	Al(s) + 3 OH⁻	-2.31	3	^[8]
Sm	Sm³⁺ + 3 e⁻	⇌	Sm(s)	-2.304	3	^[1]
Fm	Fm²⁺ + 2 e⁻	⇌	Fm	-2.3	2	^[1]
Am	Am³⁺ + e⁻	⇌	Am²⁺	-2.3	1	^[1]
Dy	Dy³⁺ + 3 e⁻	⇌	Dy(s)	-2.295	3	^[1]
Lu	Lu³⁺ + 3 e⁻	⇌	Lu(s)	-2.28	3	^[1]
Sc	ScF⁺ ₂ + 2 H⁺ + 3 e⁻	⇌	Sc(s) + 2HF(l)	-2.28	3	^[6]^: 792
Tb	Tb³⁺ + 3 e⁻	⇌	Tb(s)	-2.28	3	^[1]
Gd	Gd³⁺ + 3 e⁻	⇌	Gd(s)	-2.279	3	^[1]
H	H ₂(g) + 2 e⁻	⇌	2H⁻	-2.23	2	^[1]
Es	Es²⁺ + 2 e⁻	⇌	Es(s)	-2.23	2	^[1]
Pm	Pm²⁺ + 2 e⁻	⇌	Pm(s)	-2.2	2	^[1]
Tm	Tm³⁺ + e⁻	⇌	Tm²⁺	-2.2	1	^[1]
Dy	Dy²⁺ + 2 e⁻	⇌	Dy(s)	-2.2	2	^[1]
Ac	Ac³⁺ + 3 e⁻	⇌	Ac(s)	-2.2	3	^[1]
Yb	Yb³⁺ + 3 e⁻	⇌	Yb(s)	-2.19	3	^[1]
Cf	Cf²⁺ + 2 e⁻	⇌	Cf(s)	-2.12	2	^[1]
Nd	Nd²⁺ + 2 e⁻	⇌	Nd(s)	-2.1	2	^[1]
Ho	Ho²⁺ + 2 e⁻	⇌	Ho(s)	-2.1	2	^[1]
Sc	Sc³⁺ + 3 e⁻	⇌	Sc(s)	-2.077	3	^[9]
Al	AlF³⁻ ₆ + 3 e⁻	⇌	Al(s) + 6F⁻	-2.069	3	^[1]
Cm	Cm³⁺ + 3 e⁻	⇌	Cm(s)	-2.04	3	^[1]
Pu	Pu³⁺ + 3 e⁻	⇌	Pu(s)	-2.031	3	^[1]
Pr	Pr²⁺ + 2 e⁻	⇌	Pr(s)	-2	2	^[1]
Er	Er²⁺ + 2 e⁻	⇌	Er(s)	-2	2	^[1]
Eu	Eu³⁺ + 3 e⁻	⇌	Eu(s)	-1.991	3	^[1]
Lr	Lr³⁺ + 3 e⁻	⇌	Lr	-1.96	3	^[1]
Cf	Cf³⁺ + 3 e⁻	⇌	Cf(s)	-1.94	3	^[1]
Es	Es³⁺ + 3 e⁻	⇌	Es(s)	-1.91	3	^[1]
Pa	Pa⁴⁺ + e⁻	⇌	Pa³⁺	-1.9	1	^[1]
Am	Am²⁺ + 2 e⁻	⇌	Am(s)	-1.9	2	^[1]
Th	Th⁴⁺ + 4 e⁻	⇌	Th(s)	-1.899	4	^[1]
Fm	Fm³⁺ + 3 e⁻	⇌	Fm	-1.89	3	^[1]
N	N₂(g) + 2H₂O(l) + 4 H⁺ + 2 e⁻	⇌	2NH₃OH⁺	-1.87	2	^[6]^: 789
Np	Np³⁺ + 3 e⁻	⇌	Np(s)	-1.856	3	^[1]
Be	Be²⁺ + 2 e⁻	⇌	Be(s)	-1.847	2	^[1]
P	H ₂PO⁻ ₂ + e⁻	⇌	P(s) + 2 OH⁻	-1.82	1	^[1]
U	U³⁺ + 3 e⁻	⇌	U(s)	-1.798	3	^[1]
Sr	Sr²⁺ + 2 e⁻	⇌	Sr(Hg)	-1.793	2	^[1]
B	H ₂BO⁻ ₃ + H₂O + 3 e⁻	⇌	B(s) + 4 OH⁻	-1.79	3	^[1]
Th	ThO ₂ + 4 H⁺ + 4 e⁻	⇌	Th(s) + 2H₂O	-1.789	4	^[1]
Hf	HfO²⁺ + 2 H⁺ + 4 e⁻	⇌	Hf(s) + H₂O	-1.724	4	^[1]
P	HPO²⁻ ₃ + 2H₂O + 3 e⁻	⇌	P(s) + 5 OH⁻	-1.71	3	^[1]
Si	SiO²⁻ ₃ + 3H₂O + 4 e⁻	⇌	Si(s) + 6 OH⁻	-1.697	4	^[1]
Al	Al³⁺ + 3 e⁻	⇌	Al(s)	-1.662	3	^[1]
Ti	Ti²⁺ + 2 e⁻	⇌	Ti(s)	-1.63	2	^[7]
Zr	ZrO ₂(s) + 4 H⁺ + 4 e⁻	⇌	Zr(s) + 2H₂O	-1.553	4	^[10]
Zr	Zr⁴⁺ + 4 e⁻	⇌	Zr(s)	-1.45	4	^[10]
Ti	Ti³⁺ + 3 e⁻	⇌	Ti(s)	-1.37	3	^[11]
Ti	TiO(s) + 2 H⁺ + 2 e⁻	⇌	Ti(s) + H₂O	-1.31	2	^[6]^: 792
B	B(OH)⁻ ₄ + 4H₂O(l) + 8 e⁻	⇌	BH⁻ ₄ + 8 OH⁻	-1.24	8	^[6]^: 788
Ga	GaO(OH)⁻ ₂ + H₂O(l) + 3 e⁻	⇌	Ga(s) + 3 OH⁻	-1.22	3	^[6]^: 788
Ti	Ti ₂O ₃(s) + 2 H⁺ + 2 e⁻	⇌	2TiO(s) + H₂O	-1.23	2	^[6]^: 792
Zn	Zn(OH)²⁻ ₄ + 2 e⁻	⇌	Zn(s) + 4 OH⁻	-1.199	2	^[10]
Mn	Mn²⁺ + 2 e⁻	⇌	Mn(s)	-1.185	2	^[10]
Fe	Fe(CN)⁴⁻ ₆ + 6 H⁺ + 2 e⁻	⇌	Fe(s) + 6HCN(aq)	-1.16	2	^[12]
C	C(s) + 3H₂O(l) + 2 e⁻	⇌	CH₃OH(l) + 2 OH⁻	-1.148	2	^[6]^: 788
Cr	Cr(CN)³⁻ ₆ + e⁻	⇌	Cr(CN)⁴⁻ ₆	-1.143	1	^[6]^: 793
Te	Te(s) + 2 e⁻	⇌	Te²⁻	-1.143	2	^[13]
V	V²⁺ + 2 e⁻	⇌	V(s)	-1.13	2	^[13]
Nb	Nb³⁺ + 3 e⁻	⇌	Nb(s)	-1.099	3	^[8]
Sn	Sn(s) + 4 H⁺ + 4 e⁻	⇌	SnH ₄(g)	-1.07	4
Po	Po(s) + 2 e⁻	⇌	Po²⁻	-1.021	2	^[14]
Cr	[Cr(edta)(H₂O)]⁻ + e⁻	⇌	[Cr(edta)(H₂O)]²⁻	-0.99	1	^[6]^: 793
P	2H₃PO₄(aq) + 2 H⁺ + 2 e⁻	⇌	(H₂PO₃)₂(aq) + H₂O(l)	-0.933	2	^[6]^: 789
C	CO²⁻ ₃ + 3 H⁺ + 2 e⁻	⇌	HCO⁻ ₂ + H₂O(l)	-0.93	2	^[6]^: 788
Ti	TiO²⁺ + 2 H⁺ + 4 e⁻	⇌	Ti(s) + H₂O	-0.93	4
Si	SiO ₂(quartz) + 4 H⁺ + 4 e⁻	⇌	Si(s) + 2H₂O	-0.909	4	^[6]^: 788
Cr	Cr²⁺ + 2 e⁻	⇌	Cr(s)	-0.9	2	^[6]^: 793
B	B(OH) ₃(aq) + 3 H⁺ + 3 e⁻	⇌	B(s) + 3H₂O	-0.89	3	^[6]^: 788
Fe	Fe(OH) ₂(s) + 2 e⁻	⇌	Fe(s) + 2 OH⁻	-0.89	2	^[12]
Fe	Fe ₂O ₃(s) + 3H₂O + 2 e⁻	⇌	2Fe(OH) ₂(s) + 2 OH⁻	-0.86	2	^[12]
H	2H₂O + 2 e⁻	⇌	H ₂(g) + 2 OH⁻	-0.8277	2	^[10]
Bi	Bi(s) + 3 H⁺ + 3 e⁻	⇌	BiH ₃	-0.8	3	^[10]
Zn	Zn²⁺ + 2 e⁻	⇌	Zn(Hg)	-0.7628	2	^[10]
Zn	Zn²⁺ + 2 e⁻	⇌	Zn(s)	-0.7618	2	^[10]
Ta	Ta ₂O ₅(s) + 10 H⁺ + 10 e⁻	⇌	2Ta(s) + 5H₂O	-0.75	10
Te	2Te(s) + 2 e⁻	⇌	Te²⁻ ₂	-0.74	2	^[6]^: 790
Ni	Ni(OH) ₂(s) + 2 e⁻	⇌	Ni(s) + 2 OH⁻	-0.72	2	^[1]
Nb	Nb₂O₅(s) + 10 H⁺ + 10 e⁻	⇌	2Nb(s) + 5H₂O(l)	-0.7	10	^[6]^: 793
Ag	Ag ₂S(s) + 2 e⁻	⇌	2Ag(s) + S²⁻ (aq)	-0.69	2
Te	Te²⁻ ₂ + 4 H⁺ + 2 e⁻	⇌	2H₂Te(g)	-0.64	2	^[6]^: 790
Sb	Sb(OH)⁻ ₄ + 3 e⁻	⇌	Sb(s) + 4 OH⁻	-0.639	3	^[6]^: 789
Au	[Au(CN) ₂]⁻ + e⁻	⇌	Au(s) + 2CN⁻	-0.6	1
Ta	Ta³⁺ + 3 e⁻	⇌	Ta(s)	-0.6	3	^[8]
Pb	PbO(s) + H₂O + 2 e⁻	⇌	Pb(s) + 2 OH⁻	-0.580	2	^[8]
Ti	2TiO ₂(s) + 2 H⁺ + 2 e⁻	⇌	Ti ₂O ₃(s) + H₂O	-0.56	2	^[6]^: 792
Ga	Ga³⁺ + 3 e⁻	⇌	Ga(s)	-0.549	3	^[8]
U	U⁴⁺ + e⁻	⇌	U³⁺	-0.52	1	^[15]
P	H ₃PO ₂(aq) + H⁺ + e⁻	⇌	P(white)^{[note 1]} + 2H₂O	-0.508	1	^[10]
P	H ₃PO ₃(aq) + 2 H⁺ + 2 e⁻	⇌	H ₃PO ₂(aq) + H₂O	-0.499	2	^[10]
Ni	NiO ₂(s) + 2H₂O + 2 e⁻	⇌	Ni(OH) ₂(s) + 2 OH⁻	0.49	2	^[1]
Sb	Sb(OH)⁻ ₆ + 2 e⁻	⇌	Sb(OH)⁻ ₄ + 2 OH⁻	-0.465	2	^[6]^: 789
P	H ₃PO ₃(aq) + 3 H⁺ + 3 e⁻	⇌	P(red)^{[note 1]} + 3H₂O	-0.454	3	^[10]
Bi	Bi₂O₃(s) + 3H₂O(l) + 6 e⁻	⇌	Bi(s) + 6 OH⁻	-0.452	6	^[6]^: 789
Ta	TaF²⁻ ₇ + 7 H⁺ + 5 e⁻	⇌	Ta(s) + 7HF(l)	-0.45	5	^[6]^: 793
In	In³⁺ + 2 e⁻	⇌	In⁺	-0.444	2	^[6]^: 788
Cu	Cu(CN)⁻ ₂ + e⁻	⇌	Cu(s) + 2CN⁻	-0.44	1	^[13]
Fe	Fe²⁺ + 2 e⁻	⇌	Fe(s)	-0.44	2	^[7]
C	2CO ₂(g) + 2 H⁺ + 2 e⁻	⇌	HOOCCOOH(aq)	-0.43	2
Cr	Cr³⁺ + e⁻	⇌	Cr²⁺	-0.407	1	^[8]
Cd	Cd²⁺ + 2 e⁻	⇌	Cd(s)	-0.4	2	^[7]
Ti	Ti³⁺ + e⁻	⇌	Ti²⁺	-0.37	1	^[6]^: 792
Cu	Cu ₂O(s) + H₂O + 2 e⁻	⇌	2Cu(s) + 2 OH⁻	-0.36	2	^[10]
Pb	PbSO ₄(s) + 2 e⁻	⇌	Pb(s) + SO²⁻ ₄	-0.3588	2	^[10]
Pb	PbSO ₄(s) + 2 e⁻	⇌	Pb(Hg) + SO²⁻ ₄	-0.3505	2	^[10]
Eu	Eu³⁺ + e⁻	⇌	Eu²⁺	-0.35	1	^[15]
In	In³⁺ + 3 e⁻	⇌	In(s)	-0.34	3	^[13]
Tl	Tl⁺ + e⁻	⇌	Tl(s)	-0.34	1	^[13]
Ge	Ge(s) + 4 H⁺ + 4 e⁻	⇌	GeH ₄(g)	-0.29	4
Co	Co²⁺ + 2 e⁻	⇌	Co(s)	-0.28	2	^[10]
P	H ₃PO ₄(aq) + 2 H⁺ + 2 e⁻	⇌	H ₃PO ₃(aq) + H₂O	-0.276	2	^[10]
N	N₂(g) + 8 H⁺ + 6 e⁻	⇌	2NH⁺ ₄	-0.27	6	^[16]
V	V³⁺ + e⁻	⇌	V²⁺	-0.26	1	^[7]
Ni	Ni²⁺ + 2 e⁻	⇌	Ni(s)	-0.257	2	^[8]
S	2HSO⁻ ₄ + 2 H⁺ + 2 e⁻	⇌	S₂O²⁻ ₆ + 2H₂O(l)	-0.253	2	^[6]^: 790
As	As(s) + 3 H⁺ + 3 e⁻	⇌	AsH ₃(g)	-0.23	3	^[13]
N	N₂(g) + 5 H⁺ + 4 e⁻	⇌	N₂H⁺ ₅	-0.23	4	^[6]^: 789
Ga	Ga⁺ + e⁻	⇌	Ga(s)	-0.2	1	^[8]
Ag	AgI(s) + e⁻	⇌	Ag(s) + I⁻	-0.15224	1	^[10]
Ge	GeO₂(s) + 4 H⁺ + 4 e⁻	⇌	Ge(s) + 2H₂O(l)	-0.15	4	^[16]
Mo	MoO ₂(s) + 4 H⁺ + 4 e⁻	⇌	Mo(s) + 2H₂O	-0.15	4
Si	Si(s) + 4 H⁺ + 4 e⁻	⇌	SiH ₄(g)	-0.14	4
Sn	Sn²⁺ + 2 e⁻	⇌	Sn(s)	-0.13	2
O	O ₂(g) + H⁺ + e⁻	⇌	HO^• ₂(aq)	-0.13	1
In	In⁺ + e⁻	⇌	In(s)	-0.126	1	^[6]^: 788
Pb	Pb²⁺ + 2 e⁻	⇌	Pb(s)	-0.126	2	^[7]
W	WO ₂(s) + 4 H⁺ + 4 e⁻	⇌	W(s) + 2H₂O	-0.12	4
Ge	GeO ₂(s) + 2 H⁺ + 2 e⁻	⇌	GeO(s) + H₂O	-0.118	2	^[8]
P	P(red) + 3 H⁺ + 3 e⁻	⇌	PH ₃(g)	-0.111	3	^[10]
C	CO ₂(g) + 2 H⁺ + 2 e⁻	⇌	HCOOH(aq)	-0.11	2
Se	Se(s) + 2 H⁺ + 2 e⁻	⇌	H ₂Se(g)	-0.11	2	^[6]^: 790
C	CO ₂(g) + 2 H⁺ + 2 e⁻	⇌	CO(g) + H₂O	-0.11	2
Sn	α-SnO(s) + 2 H⁺ + 2 e⁻	⇌	Sn(s) + H₂O	-0.104	2	^[6]^: 788
Cu	Cu(NH ₃)⁺ ₂ + e⁻	⇌	Cu(s) + 2NH ₃(aq)	-0.1	1	^[13]
Nb	Nb₂O₅(s) + 10 H⁺ + 4 e⁻	⇌	2Nb³⁺ + 5H₂O(l)	-0.1	4	^[6]^: 793
W	WO ₃(aq) + 6 H⁺ + 6 e⁻	⇌	W(s) + 3H₂O	-0.09	6	^[13]
Sn	SnO ₂(s) + 2 H⁺ + 2 e⁻	⇌	α-SnO(s) + H₂O	-0.088	2	^[6]^: 788
Fe	Fe ₃O ₄(s) + 8 H⁺ + 8 e⁻	⇌	3Fe(s) + 4H₂O	-0.085	8	^[17]
V	VOH²⁺ + H⁺ + e⁻	⇌	V²⁺ + H₂O(l)	-0.082	1	^[6]^: 793
P	P(white) + 3 H⁺ + 3 e⁻	⇌	PH ₃(g)	-0.063	3	^[10]
N	N₂O(g) + H₂O(l) + 6 H⁺ + 4 e⁻	⇌	2NH₃OH⁺	-0.05	4	^[6]^: 789
Fe	Fe³⁺ + 3 e⁻	⇌	Fe(s)	-0.04	3	^[12]
C	HCOOH(aq) + 2 H⁺ + 2 e⁻	⇌	HCHO(aq) + H₂O	-0.034	2	^[6]^: 788
H	2 H⁺ + 2 e⁻	⇌	H ₂(g)	0	2
Ag	AgBr(s) + e⁻	⇌	Ag(s) + Br⁻	0.07133	1	^[10]
S	S ₄O²⁻ ₆ + 2 e⁻	⇌	2S ₂O²⁻ ₃	0.08	2
N	N ₂(g) + 2H₂O + 6 H⁺ + 6 e⁻	⇌	2NH ₄OH(aq)	0.092	6
Hg	HgO(s) + H₂O + 2 e⁻	⇌	Hg(l) + 2 OH⁻	0.0977	2
Cu	Cu(NH ₃)²⁺ ₄ + e⁻	⇌	Cu(NH ₃)⁺ ₂ + 2NH ₃(aq)	0.1	1	^[13]
Ru	Ru(NH ₃)³⁺ ₆ + e⁻	⇌	Ru(NH ₃)²⁺ ₆	0.1	1	^[15]
N	N ₂H ₄(aq) + 4H₂O + 2 e⁻	⇌	2NH⁺ ₄ + 4 OH⁻	0.11	2	^[4]
Mo	H ₂MoO ₄(aq) + 6 H⁺ + 6 e⁻	⇌	Mo(s) + 4H₂O	0.11	6
Ge	Ge⁴⁺ + 4 e⁻	⇌	Ge(s)	0.12	4
C	C(s) + 4 H⁺ + 4 e⁻	⇌	CH ₄(g)	0.13	4	^[13]
C	HCHO(aq) + 2 H⁺ + 2 e⁻	⇌	CH ₃OH(aq)	0.13	2
S	S(s) + 2 H⁺ + 2 e⁻	⇌	H ₂S(g)	0.144	2	^[6]^: 790
Sb	Sb₂O₃(s) + 6 H⁺ + 6 e⁻	⇌	2Sb(s) + 3H₂O	0.15	6	^[6]^: 789
Sn	Sn⁴⁺ + 2 e⁻	⇌	Sn²⁺	0.151	2	^[8]
S	HSO⁻ ₄ + 3 H⁺ + 2 e⁻	⇌	SO ₂(aq) + 2H₂O	0.158	2	^[6]^: 790
Cu	Cu²⁺ + e⁻	⇌	Cu⁺	0.159	1	^[13]
U	UO²⁺ ₂ + e⁻	⇌	UO⁺ ₂	0.163	1	^[15]
S	SO²⁻ ₄ + 4 H⁺ + 2 e⁻	⇌	SO ₂(aq) + 2H₂O	0.17	2
Ti	TiO²⁺ + 2 H⁺ + e⁻	⇌	Ti³⁺ + H₂O	0.19	1
Sb	SbO⁺ + 2 H⁺ + 3 e⁻	⇌	Sb(s) + H₂O	0.2	3
Fe	3Fe ₂O ₃(s) + 2 H⁺ + 2 e⁻	⇌	2Fe ₃O ₄(s) + H₂O	0.22	2	^[18]^: p.100
Ag	AgCl(s) + e⁻	⇌	Ag(s) + Cl⁻	0.22233	1	^[10]
As	H ₃AsO ₃(aq) + 3 H⁺ + 3 e⁻	⇌	As(s) + 3H₂O	0.24	3	^[6]^: 789
Ru	Ru³⁺ (aq) + e⁻	⇌	Ru²⁺ (aq)	0.249	1	^[19]
Pb	PbO₂(s) + H₂O + 2 e⁻	⇌	α-PbO(s) + 2 OH⁻	0.254	2	^[6]^: 788
Ge	GeO(s) + 2 H⁺ + 2 e⁻	⇌	Ge(s) + H₂O	0.26	2
Hg	Hg₂Cl₂(s) + 2 e⁻	⇌	2Hg(l) + 2Cl⁻	0.27	2	^[16]
U	UO⁺ ₂ + 4 H⁺ + e⁻	⇌	U⁴⁺ + 2H₂O	0.273	1	^[15]
Re	Re³⁺ + 3 e⁻	⇌	Re(s)	0.300	3	^[8]
At	At + e⁻	⇌	At⁻	0.3	1	^[20]
Bi	Bi³⁺ + 3 e⁻	⇌	Bi(s)	0.308	3	^[10]
C	2HCNO + 2 H⁺ + 2 e⁻	⇌	(CN)₂ + 2H₂O	0.330	2	^[8]
Cu	Cu²⁺ + 2 e⁻	⇌	Cu(s)	0.337	2	^[13]
V	VO²⁺ + 2 H⁺ + e⁻	⇌	V³⁺ + H₂O	0.337	1	^[6]^: 793
Sb	Sb₂O₄(s) + 2 H⁺ + 2 e⁻	⇌	Sb₂O₃(s) + H₂O(l)	0.342	2	^[6]^: 789
At	At⁺ + 2 e⁻	⇌	At^-	0.36	2	^[21]
Fe	[Fe(CN) ₆]³⁻ + e⁻	⇌	[Fe(CN) ₆]⁴⁻	0.3704	1	^[22]
C	(CN)₂ + 2 H⁺ + 2 e⁻	⇌	2HCN	0.373	2	^[8]
P	(H₂PO₃)₂(aq) + 2 H⁺ + 2 e⁻	⇌	2H₃PO₃	0.38	2	^[6]^: 789
S	2SO₂(aq) + 2 H⁺ + 2 e⁻	⇌	S₂O²⁻ ₃ + H₂O(l)	0.4	2	^[6]^: 790
O	O ₂(g) + 2H₂O + 4 e⁻	⇌	4 OH⁻(aq)	0.401	4	^[7]
Mo	H ₂MoO ₄ + 6 H⁺ + 3 e⁻	⇌	Mo³⁺ + 4H₂O	0.43	3
Ru	Ru²⁺ (aq) + 2 e⁻	⇌	Ru	0.455	2	^[19]
V	VO(OH)⁺ + 2 H⁺ + e⁻	⇌	VOH²⁺ + H₂O(l)	0.481	1	^[6]^: 793
C	CH ₃OH(aq) + 2 H⁺ + 2 e⁻	⇌	CH ₄(g) + H₂O	0.5	2
S	SO ₂(aq) + 4 H⁺ + 4 e⁻	⇌	S(s) + 2H₂O	0.5	4	^[6]^: 790
S	4SO ₂(aq) + 4 H⁺ + 8 e⁻	⇌	S₄O²⁻ ₆ + 2H₂O(l)	0.51	8	^[16]
Cu	Cu⁺ + e⁻	⇌	Cu(s)	0.52	1	^[13]
C	CO(g) + 2 H⁺ + 2 e⁻	⇌	C(s) + H₂O	0.52	2	^[6]^: 788
I	I⁻ ₃ + 2 e⁻	⇌	3I⁻	0.53	2	^[7]
Te	TeO₂(s) + 4 H⁺ + 4 e⁻	⇌	Te(s) + 2H₂O(l)	0.53	4	^[6]^: 790
Cu	Cu²⁺ + Cl⁻ + e⁻	⇌	CuCl(s)	0.54	1	^[16]
I	I ₂(s) + 2 e⁻	⇌	2I⁻	0.54	2	^[7]
Au	[AuI ₄]⁻ + 3 e⁻	⇌	Au(s) + 4I⁻	0.56	3
As	H ₃AsO ₄(aq) + 2 H⁺ + 2 e⁻	⇌	H ₃AsO ₃(aq) + H₂O	0.56	2	^[6]^: 789
S	S₂O²⁻ ₆ + 4 H⁺ + 2 e⁻	⇌	2H₂SO₃	0.569	2	^[6]^: 790
Au	[AuI ₂]⁻ + e⁻	⇌	Au(s) + 2I⁻	0.58	1
Mn	MnO⁻ ₄ + 2H₂O + 3 e⁻	⇌	MnO ₂(s) + 4 OH⁻	0.595	3	^[1]
S	S ₂O²⁻ ₃ + 6 H⁺ + 4 e⁻	⇌	2S(s) + 3H₂O	0.6	4	^[6]^: 790
Fe	Fc⁺ + e⁻	⇌	Fc(s)	0.63	1	Substantial literature variation^[23]
Mo	H ₂MoO ₄(aq) + 2 H⁺ + 2 e⁻	⇌	MoO ₂(s) + 2H₂O	0.65	2
N	HN₃(aq) + 11 H⁺ + 8 e⁻	⇌	3NH⁺ ₄	0.69	8	^[16]
O	O ₂(g) + 2 H⁺ + 2 e⁻	⇌	H ₂O ₂(aq)	0.695	2	^[8]
Sb	Sb₂O₅(s) + 4 H⁺ + 4 e⁻	⇌	Sb₂O₃(s) + 2H₂O	0.699	4	^[6]^: 789
C	+ 2 H⁺ + 2 e⁻	⇌		0.6992	2	^[10]
V	H₂V₁₀O⁴⁻ ₂₈ + 24 H⁺ + 10 e⁻	⇌	10VO(OH)⁺ + 8H₂O(l)	0.723	10	^[6]^: 793
Pt	PtCl²⁻ ₆ + 2 e⁻	⇌	PtCl²⁻ ₄ + 2Cl⁻	0.726	2	^[15]
Fe	Fe ₂O ₃(s) + 6 H⁺ + 2 e⁻	⇌	2Fe²⁺ + 3H₂O	0.728	2	^[18]^: p.100
Se	H ₂SeO ₃(aq) + 4 H⁺ + 4 e⁻	⇌	Se(s) + 3H₂O	0.74	4	^[8]
At	AtO⁺ + 2 H⁺ + 2 e⁻	⇌	At⁺ + H₂O	0.74	2	^[21]
Tl	Tl³⁺ + 3 e⁻	⇌	Tl(s)	0.741	3	^[8]
No	No³⁺ + e⁻	⇌	No²⁺	0.75	1	^[24]
Pt	PtCl²⁻ ₄ + 2 e⁻	⇌	Pt(s) + 4Cl⁻	0.758	2	^[15]
Br	BrO⁻ + H₂O(l) + 2 e⁻	⇌	Br⁻ + 2 OH⁻	0.76	2	^[6]^: 791
Po	Po⁴⁺ + 4 e⁻	⇌	Po	0.76	4	^[8]
S	(SCN)₂ + 2 e⁻	⇌	2SCN^-	0.769	2	^[25]^[8]
Fe	Fe³⁺ + e⁻	⇌	Fe²⁺	0.771	1	^[8]
Hg	Hg²⁺ ₂ + 2 e⁻	⇌	2Hg(l)	0.7973	2	^[8]
Ag	Ag⁺ + e⁻	⇌	Ag(s)	0.7996	1	^[10]
N	2NO⁻ ₃(aq) + 4 H⁺ + 2 e⁻	⇌	N ₂O ₄(g) + 2H₂O	0.803	2	^[6]^: 789
Fe	2FeO²⁻ ₄ + 5H₂O + 6 e⁻	⇌	Fe ₂O ₃(s) + 10 OH⁻	0.81	6	^[12]
Au	[AuBr ₄]⁻ + 3 e⁻	⇌	Au(s) + 4Br⁻	0.85	3
Hg	Hg²⁺ + 2 e⁻	⇌	Hg(l)	0.85	2
Ir	[IrCl ₆]²⁻ + e⁻	⇌	[IrCl ₆]³⁻	0.87	1	^[6]^: 153
Mn	MnO⁻ ₄ + H⁺ + e⁻	⇌	HMnO⁻ ₄	0.9	1
Po	Po⁴⁺ + 2 e⁻	⇌	Po²⁺	0.9	2	^[8]
Hg	2Hg²⁺ + 2 e⁻	⇌	Hg²⁺ ₂	0.91	2	^[13]
Pd	Pd²⁺ + 2 e⁻	⇌	Pd(s)	0.915	2	^[15]
Au	[AuCl ₄]⁻ + 3 e⁻	⇌	Au(s) + 4Cl⁻	0.93	3
N	NO⁻ ₃ + 3 H⁺ + 2 e⁻	⇌	HNO₂(aq)	0.94	2	^[6]^: 789
Mn	MnO ₂(s) + 4 H⁺ + e⁻	⇌	Mn³⁺ + 2H₂O	0.95	1
N	NO⁻ ₃(aq) + 4 H⁺ + 3 e⁻	⇌	NO(g) + 2H₂O(l)	0.958	3	^[7]
Au	[AuBr ₂]⁻ + e⁻	⇌	Au(s) + 2Br⁻	0.96	1
Fe	Fe ₃O ₄(s) + 8 H⁺ + 2 e⁻	⇌	3Fe²⁺ + 4H₂O	0.98	2	^[18]^: p.100
Xe	[HXeO ₆]³⁻ + 2H₂O + 2 e⁻	⇌	[HXeO ₄]⁻ + 4 OH⁻	0.99	2	^[6]^: 792^[26]
N	HNO₂(aq) + H⁺ + e⁻	⇌	NO(g) + H₂O(l)	0.996	1	^[6]^: 789
At	HAtO + H⁺ + e⁻	⇌	At + H₂O	1.0	1	^[20]
V	[VO ₂]⁺ (aq) + 2 H⁺ + e⁻	⇌	[VO]²⁺ (aq) + H₂O	1	1	^[27]
Te	H ₆TeO ₆(aq) + 2 H⁺ + 2 e⁻	⇌	TeO ₂(s) + 4H₂O	1.02	2	^[27]
N	NO₂(g) + 2 H⁺ + 2 e⁻	⇌	NO(g) + H₂O(l)	1.03	2	^[16]
Br	Br⁻ ₃ + 2 e⁻	⇌	3Br⁻	1.05	2	^[16]
Sb	Sb₂O₅(s) + 2 H⁺ + 2 e⁻	⇌	Sb₂O₄(s) + H₂O(l)	1.055	2	^[6]^: 789
I	ICl⁻ ₂ + e⁻	⇌	2Cl⁻ + I(s)	1.06	1	^[16]
Br	Br ₂(l) + 2 e⁻	⇌	2Br⁻	1.066	2	^[10]
N	N₂O₄(g) + 2 H⁺ + 2 e⁻	⇌	2HNO₂	1.07	2	^[6]^: 789
Br	Br ₂(aq) + 2 e⁻	⇌	2Br⁻	1.0873	2	^[10]
Ru	RuO ₂ + 4 H⁺ + 2 e⁻	⇌	Ru²⁺ (aq) + 2H₂O	1.120	2	^[19]
Cu	Cu²⁺ + 2CN⁻ + e⁻	⇌	Cu(CN)⁻ ₂	1.12	1	^[13]
I	IO⁻ ₃ + 5 H⁺ + 4 e⁻	⇌	HIO(aq) + 2H₂O	1.13	4	^[6]^: 791
O	H₂O₂(aq) + H⁺ + e⁻	⇌	H₂O(l) + HO•	1.14	1	^[6]^: 790
Au	[AuCl ₂]⁻ + e⁻	⇌	Au(s) + 2Cl⁻	1.15	1
Se	HSeO⁻ ₄ + 3 H⁺ + 2 e⁻	⇌	H ₂SeO ₃(aq) + H₂O	1.15	2	^[6]^: 790
Ag	Ag ₂O(s) + 2 H⁺ + 2 e⁻	⇌	2Ag(s) + H₂O	1.17	2
Cl	ClO⁻ ₃ + 2 H⁺ + e⁻	⇌	ClO ₂(g) + H₂O	1.175	1	^[6]^: 791
Xe	[HXeO ₆]³⁻ + 5H₂O + 8 e⁻	⇌	Xe(g) + 11 OH⁻	1.18	8	^[26]
Pt	Pt²⁺ + 2 e⁻	⇌	Pt(s)	1.188	2	^[15]
Cl	ClO ₂(g) + H⁺ + e⁻	⇌	HClO ₂(aq)	1.19	1	^[28]
I	2IO⁻ ₃ + 12 H⁺ + 10 e⁻	⇌	I ₂(s) + 6H₂O	1.2	10	^[16]
Mn	MnO ₂(s) + 4 H⁺ + 2 e⁻	⇌	Mn²⁺ + 2H₂O	1.224	2	^[10]
O	O ₂(g) + 4 H⁺ + 4 e⁻	⇌	2H₂O	1.229	4	^[7]
N	N₂H⁺ ₅ + 3 H⁺ + 2 e⁻	⇌	2NH⁺ ₄	1.28	2	^[6]^: 789
Cl	ClO⁻ ₄ + 2 H⁺ + 2 e⁻	⇌	ClO⁻ ₃ + H₂O	1.23	2	^[29]
Ru	[Ru(bipy) ₃]³⁺ + e⁻	⇌	[Ru(bipy) ₃]²⁺	1.24	1	^[1]
Xe	[HXeO ₄]⁻ + 3H₂O + 6 e⁻	⇌	Xe(g) + 7 OH⁻	1.24	6	^[6]^: 792^[26]
N	2NO⁻ ₃ + 12 H⁺ + 10 e⁻	⇌	N₂(g) + 6H₂O(l)	1.25	10	^[6]^: 789
Tl	Tl³⁺ + 2 e⁻	⇌	Tl⁺	1.25	2	^[6]^: 788
N	2HNO₂(aq) + 4 H⁺ + 4 e⁻	⇌	N₂O(g) + 3H₂O(l)	1.297	4	^[6]^: 789
Cr	Cr ₂O²⁻ ₇ + 14 H⁺ + 6 e⁻	⇌	2Cr³⁺ + 7H₂O	1.38	6	^[6]^: 793
N	NH₃OH⁺ + 2 H⁺ + 2 e⁻	⇌	NH⁺ ₄ + H₂O(l)	1.35	2	^[6]^: 789
Cl	Cl ₂(g) + 2 e⁻	⇌	2Cl⁻	1.36	2	^[7]
Ru	RuO⁻ ₄(aq) + 8 H⁺ + 5 e⁻	⇌	Ru²⁺ (aq) + 4H₂O	1.368	5	^[19]
Ru	RuO ₄ + 4 H⁺ + 4 e⁻	⇌	RuO ₂ + 2H₂O	1.387	4	^[19]
Co	CoO ₂(s) + 4 H⁺ + e⁻	⇌	Co³⁺ + 2H₂O	1.42	1
N	2NH ₃OH⁺ + H⁺ + 2 e⁻	⇌	N ₂H⁺ ₅ + 2H₂O	1.42	2	^[4]
I	2HIO(aq) + 2 H⁺ + 2 e⁻	⇌	I ₂(s) + 2H₂O	1.44	2	^[6]^: 791
Br	BrO⁻ ₃ + 5 H⁺ + 4 e⁻	⇌	HBrO(aq) + 2H₂O	1.447	4	^[6]^: 791
Pb	β-PbO ₂(s) + 4 H⁺ + 2 e⁻	⇌	Pb²⁺ + 2H₂O	1.46	2	^[13]
Pb	α-PbO ₂(s) + 4 H⁺ + 2 e⁻	⇌	Pb²⁺ + 2H₂O	1.468	2	^[13]
Br	2BrO⁻ ₃ + 12 H⁺ + 10 e⁻	⇌	Br ₂(l) + 6H₂O	1.48	10
At	HAtO₃ + 4 H⁺ + 4 e⁻	⇌	HAtO + 2H₂O	1.5	4	^[20]
Mn	MnO⁻ ₄ + 8 H⁺ + 5 e⁻	⇌	Mn²⁺ + 4H₂O	1.51	5	^[16]
O	HO^• ₂ + H⁺ + e⁻	⇌	H ₂O ₂(aq)	1.51	1
Au	Au³⁺ + 3 e⁻	⇌	Au(s)	1.52	3
Ru	RuO²⁻ ₄(aq) + 8 H⁺ + 4 e⁻	⇌	Ru²⁺ (aq) + 4H₂O	1.563	4	^[19]
N	2NO(g) + 2 H⁺ + 2 e⁻	⇌	N₂O(g) + H₂O(l)	1.59	2	^[6]^: 789
Ni	NiO ₂(s) + 2 H⁺ + 2 e⁻	⇌	Ni²⁺ + 2 OH⁻	1.59	2
Ce	Ce⁴⁺ + e⁻	⇌	Ce³⁺	1.61	1
Cl	2HClO(aq) + 2 H⁺ + 2 e⁻	⇌	Cl ₂(g) + 2H₂O	1.63	2	^[28]
I	IO⁻ ₄ + 2 H⁺ + 2 e⁻	⇌	IO⁻ ₃ + H₂O	1.64	2	^[29]
Ag	Ag ₂O ₃(s) + 6 H⁺ + 4 e⁻	⇌	2Ag⁺ + 3H₂O	1.67	4
Cl	HClO ₂(aq) + 2 H⁺ + 2 e⁻	⇌	HClO(aq) + H₂O	1.67	2	^[28]
Pb	Pb⁴⁺ + 2 e⁻	⇌	Pb²⁺	1.69	2	^[13]
Mn	MnO⁻ ₄ + 4 H⁺ + 3 e⁻	⇌	MnO ₂(s) + 2H₂O	1.7	3	^[16]
Br	BrO⁻ ₄ + 2 H⁺ + 2 e⁻	⇌	BrO⁻ ₃ + H₂O	1.74	2	^[29]
Ag	AgO(s) + 2 H⁺ + e⁻	⇌	Ag⁺ + H₂O	1.77	1
N	N₂O(g) + 2 H⁺ + 2 e⁻	⇌	N₂(g) + H₂O(l)	1.77	2	^[6]^: 789
O	H ₂O ₂(aq) + 2 H⁺ + 2 e⁻	⇌	2H₂O	1.78	2	^[28]
Au	Au⁺ + e⁻	⇌	Au(s)	1.83	1	^[13]
Co	Co³⁺ + e⁻	⇌	Co²⁺	1.92	1	^[8]
Ag	Ag²⁺ + e⁻	⇌	Ag⁺	1.98	1	^[13]
O	S ₂O²⁻ ₈ + 2 e⁻	⇌	2SO²⁻ ₄	2.01	2	^[10]
O	O ₃(g) + 2 H⁺ + 2 e⁻	⇌	O ₂(g) + H₂O	2.075	2	^[15]
Mn	HMnO⁻ ₄ + 3 H⁺ + 2 e⁻	⇌	MnO ₂(s) + 2H₂O	2.09	2
Xe	XeO ₃(aq) + 6 H⁺ + 6 e⁻	⇌	Xe(g) + 3H₂O	2.12	6	^[6]^: 792^[26]
Xe	H ₄XeO ₆(aq) + 8 H⁺ + 8 e⁻	⇌	Xe(g) + 6H₂O	2.18	8	^[6]^: 792^[26]
Fe	FeO²⁻ ₄ + 8 H⁺ + 3 e⁻	⇌	Fe³⁺ + 4H₂O	2.2	3	^[30]
Xe	XeF ₂(aq) + 2 H⁺ + 2 e⁻	⇌	Xe(g) + 2HF(aq)	2.32	2	^[26]^[28]
O	HO• + H⁺ + e⁻	⇌	H₂O(l)	2.38	1	^[6]^: 790
Xe	H ₄XeO ₆(aq) + 2 H⁺ + 2 e⁻	⇌	XeO ₃(aq) + 3H₂O	2.42	2	^[26]^[6]^: 792
F	F ₂(g) + 2 e⁻	⇌	2F⁻	2.87	2	^[6]^: 153^[7]^[13]
Cm	Cm⁴⁺ + e^–	⇌	Cm³⁺	3.0	1	Estimated^[3]
F	F ₂(g) + 2 H⁺ + 2 e⁻	⇌	2HF(aq)	3.077	2	^[3]
Tb	Tb⁴⁺ + e^–	⇌	Tb³⁺	3.1	1	Estimated^[3]
Pr	Pr⁴⁺ + e^–	⇌	Pr³⁺	3.2	1	Estimated^[3]
Kr	KrF ₂(aq) + 2 e⁻	⇌	Kr(g) + 2F⁻ (aq)	3.27	2	Estimated^[31]

Notes[edit]

^ ^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[edit]

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am ^an ^ao ^ap ^aq ^ar ^as ^at ^au ^av ^aw ^ax ^ay ^az ^ba ^bb ^bc ^bd ^be ^bf ^bg ^bh ^bi ^bj ^bk ^bl ^bm ^bn ^bo ^bp ^bq ^br ^bs ^bt ^bu ^bv Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3.
^ Greenwood and Earnshaw, p. 1263
^ ^a ^b ^c ^d ^e Bratsch, Stephen G. (July 29, 1988) [1 March 1988]. "Standard electrode potentials and temperature coefficients in water at 298.15 K" (PDF). Journal of Physical and Chemical Reference Data. 18 (1). American Institute of Physics (published 1989): 1–21. doi:10.1063/1.555839 – via NIST.
^ ^a ^b ^c ^d Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q 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.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am ^an ^ao ^ap ^aq ^ar ^as ^at ^au ^av ^aw ^ax ^ay ^az ^ba ^bb ^bc ^bd ^be ^bf ^bg ^bh ^bi ^bj ^bk ^bl ^bm ^bn ^bo ^bp ^bq ^br ^bs ^bt ^bu ^bv ^bw ^bx ^by ^bz ^ca ^cb ^cc ^cd ^ce Atkins, Peter; Overton, Tina; Rourke, Jonathan; Weller, Mark; Armstrong, Fraser; Hagerman, Michael (2010). Inorganic Chemistry (5th ed.). New York: W. H. Freeman. ISBN 978-1-42-921820-7.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Atkins, Peter W. (1997). Physical Chemistry (6th ed.). W.H. Freeman. ISBN 9780716734659.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v Petr Vanysek. "Electrochemical series" (PDF). depa.fquim.unam.mx. Archived from the original (PDF) on 2021-09-16.
^ David R. Lide, ed., CRC Handbook of Chemistry and Physics, Internet Version 2005, http://www.hbcpnetbase.com Archived 2017-07-24 at the Wayback Machine, CRC Press, Boca Raton, FL, 2005.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab Vanýsek, Petr (2012). "Electrochemical Series". In Haynes, William M. (ed.). Handbook of Chemistry and Physics (93rd ed.). CRC Press. pp. 5–80. ISBN 9781439880494.
^ Aylward, Gordon; Findlay, Tristan (2008). SI Chemical Data (6th ed.). Wiley. ISBN 978-0-470-81638-7.
^ ^a ^b ^c ^d ^e "compounds information". Iron. WebElements Periodic Table of the Elements.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u Bard, Allen J.; Parsons, Roger; Jordan, Joseph (1985). Standard Potentials in Aqueous Solution. CRC Press. ISBN 978-0-8247-7291-8.
^ Brown, Susan A.; Brown, Paul L. (2020). "The pH-potential diagram for polonium". The Aqueous Chemistry of Polonium and the Practical Application of its Thermochemistry. Elsevier. doi:10.1016/b978-0-12-819308-2.00004-8. ISBN 978-0-12-819308-2. S2CID 213141476.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Bard, A.J.; Faulkner, L.R. (2001). Electrochemical Methods. Fundamentals and Applications (2nd ed.). Wiley. ISBN 9781118312803.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Lee, J. L. (1983) [1977]. A New Concise Inorganic Chemistry (3rd ed.). London / Wokingham, Berkshire: English Language Book Society & Van Nostrand Reinhold (UK). p. 107. ISBN 0-442-30179-0. OL 4079768W – via the Internet Archive.
^ Pourbaix, Marcel (1966). Atlas of Electrochemical Equilibria in Aqueous Solutions. Houston, Texas; Cebelcor, Brussels: NACE International. OCLC 475102548.
^ ^a ^b ^c Pang, Suh Cem; Chin, Suk Fun; Anderson, Marc A. (July 2007). "Redox equilibria of iron oxides in aqueous-based magnetite dispersions: Effect of pH and redox potential". J. Colloid Interface Sci. 311 (1): 94–101. Bibcode:2007JCIS..311...94P. doi:10.1016/j.jcis.2007.02.058. PMID 17395194. Retrieved 2017-03-26.
^ ^a ^b ^c ^d ^e ^f Greenwood and Earnshaw, p. 1077
^ ^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.
^ ^a ^b Champion, J.; Alliot, C.; Renault, E.; Mokili, B. M.; Chérel, M.; Galland, N.; Montavon, G. (2009-12-16). "Astatine Standard Redox Potentials and Speciation in Acidic Medium" (PDF). The Journal of Physical Chemistry A. 114 (1). American Chemical Society (ACS): 576–582. doi:10.1021/jp9077008. ISSN 1089-5639. PMID 20014840. S2CID 15738065.
^ 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.
^ Pavlishchuk, Vitaly V.; Addison, Anthony W. (January 2000). "Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25°C". Inorganica Chimica Acta. 298 (1): 97–102. doi:10.1016/S0020-1693(99)00407-7.
^ Toyoshima, A.; Kasamatsu, Y.; Tsukada, K.; Asai, M.; Kitatsuji, Y.; Ishii, Y.; Toume, H.; Nishinaka, I.; Haba, H.; Ooe, K.; Sato, W.; Shinohara, A.; Akiyama, K.; Nagame, Y. (8 July 2009). "Oxidation of element 102, nobelium, with flow electrolytic column chromatography on an atom-at-a-time scale". Journal of the American Chemical Society. 131 (26): 9180–1. doi:10.1021/ja9030038. PMID 19514720.
^ Kaufmann, H. P. (1925). "Das freie Rhodan und seine Anwendung in der Maßanalyse. Eine neue Kennzahl der Fette" [Unbound rhodanium and its application to elemental analysis: A new measurement technique for fats]. Archiv der Pharmazie und Berichte der Deutschen Pharmazeutischen Gesellschaft (in German). 263: 675–721 – via HathiTrust.
^ ^a ^b ^c ^d ^e ^f ^g "compounds information". Xenon. WebElements Periodic Table of the Elements.
^ ^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.
^ ^a ^b ^c ^d ^e Ghosh, Abhik; Berg, Steffen (2014). Arrow Pushing in Inorganic Chemistry: A logical approach to the chemistry of the main-group elements. Hoboken: Wiley. p. 12. ISBN 978-1-118-17398-5.
^ ^a ^b ^c Appelman, Evan H. (1973-04-01). "Nonexistent compounds. Two case histories". Accounts of Chemical Research. 6 (4). American Chemical Society (ACS): 113–117. doi:10.1021/ar50064a001. ISSN 0001-4842.
^ Courtney, Arlene. "Oxidation Reduction Chemistry of the Elements". Ch 412 Advanced Inorganic Chemistry: Reading Materials. Western Oregon University.
^ 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.

External links[edit]

Chemistry LibreTexts (2021-04-26). "P1: Standard Reduction Potentials by Element". Chemistry LibreTexts. Retrieved 2021-11-30.
California State University, Northridge (CSUN). "Standard Reduction Potentials" (PDF). csun.edu. Archived (PDF) from the original on 2017-12-15. Retrieved 2021-11-30.
Wardman, Peter (1989). "Reduction potentials of one-electron couples involving free radicals in aqueous solution" (PDF). srd.nist.gov. Archived (PDF) from the original on 2022-10-09. Retrieved 2021-11-30.
http://www.jesuitnola.org/upload/clark/Refs/red_pot.htm Archived 2008-07-20 at the Wayback Machine
https://web.archive.org/web/20150924015049/http://www.fptl.ru/biblioteka/spravo4niki/handbook-of-Chemistry-and-Physics.pdf
http://hyperphysics.phy-astr.gsu.edu/Hbase/tables/electpot.html#c1

[rwP-16] 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.

[CRC-1] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am ^an ^ao ^ap ^aq ^ar ^as ^at ^au ^av ^aw ^ax ^ay ^az ^ba ^bb ^bc ^bd ^be ^bf ^bg ^bh ^bi ^bj ^bk ^bl ^bm ^bn ^bo ^bp ^bq ^br ^bs ^bt ^bu ^bv Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3.

[Greenwood1263-2] Greenwood and Earnshaw, p. 1263

[VanSrc-3] Bratsch, Stephen G. (July 29, 1988) [1 March 1988]. "Standard electrode potentials and temperature coefficients in water at 298.15 K" (PDF). Journal of Physical and Chemical Reference Data. 18 (1). American Institute of Physics (published 1989): 1–21. doi:10.1063/1.555839 – via NIST.

[Gre-4] Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.

[van92-5] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q 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.

[AS5-6] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am ^an ^ao ^ap ^aq ^ar ^as ^at ^au ^av ^aw ^ax ^ay ^az ^ba ^bb ^bc ^bd ^be ^bf ^bg ^bh ^bi ^bj ^bk ^bl ^bm ^bn ^bo ^bp ^bq ^br ^bs ^bt ^bu ^bv ^bw ^bx ^by ^bz ^ca ^cb ^cc ^cd ^ce Atkins, Peter; Overton, Tina; Rourke, Jonathan; Weller, Mark; Armstrong, Fraser; Hagerman, Michael (2010). Inorganic Chemistry (5th ed.). New York: W. H. Freeman. ISBN 978-1-42-921820-7.

[Atk-7] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Atkins, Peter W. (1997). Physical Chemistry (6th ed.). W.H. Freeman. ISBN 9780716734659.

[van??-8] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v Petr Vanysek. "Electrochemical series" (PDF). depa.fquim.unam.mx. Archived from the original (PDF) on 2021-09-16.

[9] David R. Lide, ed., CRC Handbook of Chemistry and Physics, Internet Version 2005, http://www.hbcpnetbase.com Archived 2017-07-24 at the Wayback Machine, CRC Press, Boca Raton, FL, 2005.

[van-10] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab Vanýsek, Petr (2012). "Electrochemical Series". In Haynes, William M. (ed.). Handbook of Chemistry and Physics (93rd ed.). CRC Press. pp. 5–80. ISBN 9781439880494.

[si-11] Aylward, Gordon; Findlay, Tristan (2008). SI Chemical Data (6th ed.). Wiley. ISBN 978-0-470-81638-7.

[webelements_fe-12] "compounds information". Iron. WebElements Periodic Table of the Elements.

[Bar-13] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u Bard, Allen J.; Parsons, Roger; Jordan, Joseph (1985). Standard Potentials in Aqueous Solution. CRC Press. ISBN 978-0-8247-7291-8.

[14] Brown, Susan A.; Brown, Paul L. (2020). "The pH-potential diagram for polonium". The Aqueous Chemistry of Polonium and the Practical Application of its Thermochemistry. Elsevier. doi:10.1016/b978-0-12-819308-2.00004-8. ISBN 978-0-12-819308-2. S2CID 213141476.

[Bar2-15] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Bard, A.J.; Faulkner, L.R. (2001). Electrochemical Methods. Fundamentals and Applications (2nd ed.). Wiley. ISBN 9781118312803.

[Lee-17] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Lee, J. L. (1983) [1977]. A New Concise Inorganic Chemistry (3rd ed.). London / Wokingham, Berkshire: English Language Book Society & Van Nostrand Reinhold (UK). p. 107. ISBN 0-442-30179-0. OL 4079768W – via the Internet Archive.

[Pou-18] Pourbaix, Marcel (1966). Atlas of Electrochemical Equilibria in Aqueous Solutions. Houston, Texas; Cebelcor, Brussels: NACE International. OCLC 475102548.

[Pang2007-19] Pang, Suh Cem; Chin, Suk Fun; Anderson, Marc A. (July 2007). "Redox equilibria of iron oxides in aqueous-based magnetite dispersions: Effect of pH and redox potential". J. Colloid Interface Sci. 311 (1): 94–101. Bibcode:2007JCIS..311...94P. doi:10.1016/j.jcis.2007.02.058. PMID 17395194. Retrieved 2017-03-26.

[Greenwood1077-20] ^ ^a ^b ^c ^d ^e ^f Greenwood and Earnshaw, p. 1077

[:0-21] 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.

[:2-22] Champion, J.; Alliot, C.; Renault, E.; Mokili, B. M.; Chérel, M.; Galland, N.; Montavon, G. (2009-12-16). "Astatine Standard Redox Potentials and Speciation in Acidic Medium" (PDF). The Journal of Physical Chemistry A. 114 (1). American Chemical Society (ACS): 576–582. doi:10.1021/jp9077008. ISSN 1089-5639. PMID 20014840. S2CID 15738065.

[23] 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.

[24] Pavlishchuk, Vitaly V.; Addison, Anthony W. (January 2000). "Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25°C". Inorganica Chimica Acta. 298 (1): 97–102. doi:10.1016/S0020-1693(99)00407-7.

[25] Toyoshima, A.; Kasamatsu, Y.; Tsukada, K.; Asai, M.; Kitatsuji, Y.; Ishii, Y.; Toume, H.; Nishinaka, I.; Haba, H.; Ooe, K.; Sato, W.; Shinohara, A.; Akiyama, K.; Nagame, Y. (8 July 2009). "Oxidation of element 102, nobelium, with flow electrolytic column chromatography on an atom-at-a-time scale". Journal of the American Chemical Society. 131 (26): 9180–1. doi:10.1021/ja9030038. PMID 19514720.

[26] Kaufmann, H. P. (1925). "Das freie Rhodan und seine Anwendung in der Maßanalyse. Eine neue Kennzahl der Fette" [Unbound rhodanium and its application to elemental analysis: A new measurement technique for fats]. Archiv der Pharmazie und Berichte der Deutschen Pharmazeutischen Gesellschaft (in German). 263: 675–721 – via HathiTrust.

[webelements_xe-27] ^ ^a ^b ^c ^d ^e ^f ^g "compounds information". Xenon. WebElements Periodic Table of the Elements.

[Cotton-28] 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.

[AP-29] Ghosh, Abhik; Berg, Steffen (2014). Arrow Pushing in Inorganic Chemistry: A logical approach to the chemistry of the main-group elements. Hoboken: Wiley. p. 12. ISBN 978-1-118-17398-5.

[:1-30] Appelman, Evan H. (1973-04-01). "Nonexistent compounds. Two case histories". Accounts of Chemical Research. 6 (4). American Chemical Society (ACS): 113–117. doi:10.1021/ar50064a001. ISSN 0001-4842.

[wou-31] Courtney, Arlene. "Oxidation Reduction Chemistry of the Elements". Ch 412 Advanced Inorganic Chemistry: Reading Materials. Western Oregon University.

[32] 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.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[note 1]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

[29]

Table of standard electrode potentials[edit]

See also[edit]

Notes[edit]

References[edit]

External links[edit]