Electrochemical potential 157620 219672623 2008-06-16T10:25:48Z Mpfiz 7122114 interwiki In [[electrochemistry]], the '''electrochemical potential''', <math>\bar{\mu}</math>, sometimes confusingly abbreviated to ECP, is a [[thermodynamic]] measure that combines the concepts of energy stored in the form of [[chemical potential]] and [[electric charge|electrostatics]]. It is important in biological processes that involve [[molecule|molecular]] [[diffusion]] across membranes, in electroanalytical chemistry, and industrial applications such as batteries and fuel cells. It represents one of the many interchangeable forms of [[potential energy]] through which energy may be [[conservation of energy|conserved]]. Electrochemical potential is expressed in the unit of [[Joule|J]]/[[Mole (unit)|mol]]. In generic terms, electrochemical potential is the [[mechanical work]] done in bringing 1 mole of an ion from a [[standard state]] to a specified [[concentration]] and [[electrical potential]]. By an [[IUPAC]] definition<ref>IUPAC Gold Book, http://goldbook.iupac.org/E01945.html</ref>, it is the partial molar Gibbs energy of the substance at the specified electric potential, where the substance is in a specified phase. Electrochemical potential can be expressed as :<math>\bar{\mu}_i=\mu_i + z_iF\Phi</math>, where <math>\mu_i</math> is the [[chemical potential]], <math>z_i</math> is the valency of the ion, <math>F</math> is Faraday's constant, and <math>\Phi</math> is electrostatic potential. In [[cell membranes]], the electrochemical potential is the sum of the [[chemical potential]] and the [[membrane potential]]. ==Incorrect usage== The term ''electrochemical potential'' is sometimes used in the meaning of electrode potential (either of a corroding electrode, an electrode with a non-zero net reaction, or an electrode at equilibrium). Such a usage can lead to confusion. The measured electrode potential does not equal the change of the electrochemical potential (see [[Galvani potential]]). Therefore, the recent literature usually expands the abbreviation ECP as "electrochemical corrosion potential". For electrode at equilibrium, the phrase of equilibrium or reversible potential of the electrode is used. ==See also== [[Electrochemical gradient]] ==External links== [http://www.life.uiuc.edu/crofts/bioph354/lect9.html Electrochemical potential] - lecture notes from University of Illinois at Urbana-Champaign ==References== {{Reflist}} [[category:electrochemistry]] [[category:thermodynamics]] [[de:Elektrochemisches Potenzial]] [[fr:potentiel électrochimique]] [[hu:Elektrokémiai potenciál]] [[it:Potenziale elettrochimico]] [[ja:電子化学ポテンシャル]] [[pl:Potencjał elektrochemiczny]]