Aqueous Standard Reduction Potentials

James Richard Fromm

Electrode Couple	E0, V	dE0/dT, mV/K
Na+ + e- Na	-2.7144	-0.758
Mg++ + 2e- Mg	-2.3568	+0.208
Al+++ + 3e- Al	-1.676	+0.532
Zn++ + 2e- Zn	-0.7621	+0.119
Fe++ + 2e- Fe	-0.4089	+0.178
Cd++ + 2e- Cd	-0.4022	-0.030
Tl+ + e- Tl	-0.3358	-1.313
Sn++ + 2e- Sn	-0.1410	-0.322
Pb++ + 2e- Pb	-0.1266	-0.215
2H+ + 2e- H2(SHE)	0.0000	0.000
S4O6-- + 2e- 2S2O3--	+0.0238	-1.32
Sn++++ + 2e- Sn--	+0.1539	-0.159
SO4-- + 4H+ + 2e- H2O + H2SO3(aq)	+0.1576	+0.784
Cu++ + e- Cu+	+0.1607	+0.776
S + 2H+ + 2e- H2S	+0.1739	-0.224
AgCl + e- Ag + Cl-	+0.2221	-0.648
Saturated Calomel (SCE)	+0.2412	-0.661
UO2++ + 4H+ + 2e- U4+ + 4H2O	+0.2682	-1.572
Hg2Cl2 + 2e- 2Cl- + 2Hg	+0.2680	-0.301
Bi+++ + 3e- Bi	+0.286	---
Cu++ + 2e- Cu	+0.3394	+0.011
Fe(CN)6--- + e- Fe(CN)6----	+0.3557	-2.494
Cu+ + e- Cu	+0.5180	-0.754
I2 + 2e- 2I-	+0.5345	-0.126
I--- + 2e- 3I-	+0.5354	-0.187
H3AsO4(aq) + 2H+ + 2e- H3AsO3(aq) + H2O	+0.5748	-0.258
2HgCl2 + 4H+ + 2e- Hg2Cl2 + 2Cl-	+0.6011	+0.149
Hg2SO4 + 2e- 2Hg + SO4--	+0.6152	-0.825
I2(aq) + 2e- 2I-	+0.6195	-0.443
O2 + 2H+ + 2e- H2O2(l)	+0.6237	-1.172
O2 + 2H+ + 2e- H2O2(aq)	+0.6945	-0.317
Fe+++ + e- Fe++	+0.769	+1.170
Hg2++ + 2e- Hg	+0.7955	-0.721
Ag+ + e- Ag	+0.7991	-0.989
Hg++ + 2e- Hg	+0.8519	-0.116
2Hg++ + 2e- Hg2++	+0.9083	+0.094
NO3- + 3H+ + 2e- HNO2(aq) + H2O	+0.9275	-0.371
VO2+ + 2H+ + e- VO++ + H2O	+1.0004	-0.902
HNO2(aq) + H+ + e- NO + H2O	+1.0362	-0.826
Br2(l) + 2e- 2Br-	+1.0775	-0.612
Br2(aq) + 2e- 2Br-	+1.0978	-0.176
2IO3- + 12H+ + 10e- 6H2O + I2	+1.2093	-0.245
O2 + 4H+ + 4e- 2H2O	+1.2288	-0.846
MnO2 + 4H+ + 2e- Mn++ + 2H2O	+1.1406	-0.643
Cl2 + 2e- 2Cl-	+1.3601	-1.248
MnO4- + 8H+ + 5e- 4H2O + Mn++	+1.5119	-0.646
2BrO3- + 12H+ + 10e- 6H2O + Br2	+1.5131	-0.252
Ce++++ + e- Ce+++	+1.7432	+0.318

Main Tables

Auxiliary Table