Standard electrode potential (data page)

• Temperature 298.15 K (25.00 °C; 77.00 °F);
• Effective concentration (activity) 1 mol/dm³ 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 (0.99 atm; 1.0 bar)).

Variations from these ideal conditions affect measured voltage via the Nernst equation.

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.