Standard electrode potential (E°) (standard reduction potentials) are defined by measuring the potential relative to a standard hydrogen electrode using 1 mol solution at 25 °C. The convention is to designate the cell so that the oxidised form is written first. For example,
The e.m.f. of this cell is -0.76 V and the standard electrode potential of the Zn2+|Zn half cell is -0.76 V.
Generalic, Eni. "Standard electrode potential." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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