Reduction Half-Reaction	Eo', V
½O2 + 2H+ + 2e- → H2O	0.816
Fe3+ + e- → Fe2+	0.771
Cytochrome a3(Fe3+) + e- → Cytochrome a3(Fe2+)	0.350
Cytochrome a(Fe3+) + e- → Cytochrome a(Fe2+)	0.290
Cytochrome c(Fe3+) + e- → Cytochrome c(Fe2+)	0.254
Cytochrome c1(Fe3+) + e- → Cytochrome c1(Fe2+)	0.220
CoQH⋅ + H+ + e- → CoQH2	0.190
CoQ + 2H+ + 2e- → CoQH2	0.060
Cytochrome bH(Fe3+) + e- → Cytochrome bH(Fe2+)	0.050
Fumarate + 2H+ + 2e- → Succinate	0.031
CoQ + H+ + e- → CoQH⋅	0.030
FAD + 2H+ + 2e- → FADH2	0.003-0.091*
Cytochrome bL(Fe3+) + e- → Cytochrome bL(Fe2+)	-0.100
Oxaloacetate + 2H+ + 2e- → Malate	-0.166
Pyruvate + 2H+ + 2e- → Lactate	-0.185
Acetaldehyde + 2H+ + 2e- → Ethanol	-0.197
FMN + 2H+ + 2e- → FMNH2	-0.219
FAD + 2H+ + 2e- → FADH2	-0.219
1,3-bisphosphoglycerate + 2H+ + 2e- → Glyceraldehyde-3-phosphate + Pi	-0.290
NAD+ + 2H+ + 2e- → NADH + H+	-0.320
NADP+ + 2H+ + 2e- → NADPH+ + H+	-0.320
α-Ketoglutarate + CO2 + 2H+ + 2e- → Isocitrate	-0.380
Succinate + CO2 + 2H+ + 2e- → α-Ketoglutarate + H2O	-0.670
* Reduction potential values vary for bound FAD in various flavoproteins.