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Electrode potential, ''E'', in electrochemistry, according to an IUPAC definition,〔IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006- ) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. . (Entry: "Electrode Potential" )〕 is the electromotive force of a cell built of two electrodes: * on the left-hand side is the standard hydrogen electrode, and * on the right-hand side is the electrode the potential of which is being defined. By convention: :''E''Cell = ''E''Cathode − ''E''Anode From the above, for the cell with the standard hydrogen electrode (potential of 0 by convention), one obtains: :''E''Cell = ''E''Right − 0 = ''E''Electrode The left-right convention is consistent with the international agreement that redox potentials be given for reactions written in the form of reduction half-reactions. Electrode potential is measured in volts (V). == Origin and interpretation== Electrode potential appears at the interface between an electrode and electrolyte due to the transfer of charged species across the interface, specific adsorption of ions at the interface, and specific adsorption/orientation of polar molecules, including those of the solvent. Electrode potential is the electric potential on an electrode component. In a cell, there will be an electrode potential for the cathode, and an electrode potential for the anode. The difference between the two electrode potentials equals the cell potential. ''E''Cell = ''E''Cathode − ''E''Anode The measured electrode potential may be either that at equilibrium on the working electrode ("reversible potential"), or a potential with a non-zero net reaction on the working electrode but zero net current ("corrosion potential", "mixed potential"), or a potential with a non-zero net current on the working electrode (like in galvanic corrosion or voltammetry). Reversible potentials can be sometimes converted to the standard electrode potential for a given electroactive species by extrapolation of the measured values to the standard state. The value of the electrode potential under non-equilibrium depends on the nature and composition of the contacting phases, and on the kinetics of electrode reactions at the interface (see Butler-Volmer equation). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Electrode potential」の詳細全文を読む スポンサード リンク
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