The work, in joules/mole, done in bringing 1 mole of an ion from a standard state (infinitely separated) to a specified concentration and electrical potential. Generally the measurement of interest is, however, the electrochemical potential difference between two points (e.g. inside and outside the cell). If there is no electrical potential difference, or if the molecule is uncharged, the electrochemical potential reduces to the chemical potential difference. If the system is at equilibrium the electrochemical potential difference will be zero and the Nernst equation can be used.
Subjects: Medicine and Health — Chemistry.