Nernst equation


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Nernst e·qua·tion

(nārnst),
the equation relating the equilibrium potential of electrodes to ion concentrations; the equation relating the electrical potential and concentration gradient of an ion across a permeable membrane at equilibrium: E = [RT / nF] [ln (C1/C 2)], where E = potential, R = absolute gas constant, T = absolute temperature, n = valence, F = the Faraday, ln = the natural logarithm, and C1 and C2 are the ion concentrations on the two sides; in nonideal solutions, concentration should be replaced by activity.
See also: activity (2).

Nernst e·qua·tion

(nernst ĕ-kwā'zhŭn)
The equation relating the equilibrium potential of electrodes to ion concentrations; the equation relating the electrical potential and concentration gradient of an ion across a permeable membrane at equilibrium: E = [RT/nF] [ln (C1/C2)], where E = potential, R = absolute gas constant, T = absolute temperature, n = valence, F = the Faraday, ln = the natural logarithm, and C1 and C2 are the ion concentrations on the two sides; in nonideal solutions, concentration should be replaced by activity.
See also: activity (2)

Nernst,

Walther, German physicist and Nobel laureate, 1864-1941.
Nernst equation - the equation relating the electrical potential and concentration gradient of an ion across a permeable membrane at equilibrium.
Nernst potential
Nernst theory - that the passage of an electric current through tissues causes a dissociation of the ions.
References in periodicals archive ?
He is famous for developing the Nernst Equation in 1887.
In electrochemistry, the Nernst equation is an equation that relates the reduction potential of an electrochemical reaction (half-cell or full cell reaction) to the standard electrode potential, temperature, and activities (often approximated by concentrations) of the chemical species undergoing reduction and oxidation.
The linear relationship between the concentration ratio of [I.sub.2]/KI solution and the ORP value was obtained through Nernst equation. [I.sub.2]/KI electrode solutions with concentration ratios of 1:4 (0.1 M [I.sub.2] and 0.4 M KI), 1:8 (0.1 M [I.sub.2] and 0.8 M KI), 1:12 (0.1 M [I.sub.2] and 1.2 M KI), 1:16 (0.1 M [I.sub.2] and 1.6 M KI), and 1:20 (0.1 M [I.sub.2] and 2 M KI) were used to verify the linear relationship.
[21] has applied the Nernst equation, mass balance equation of redox reaction and Faraday's law of electrolysis to establish the relationship between the half-cell redox concentration of Ce(IV)/Ce(III) and the ORP during electrolysis.
The half-cell potential for each reaction is determined with the Nernst equation. The resulting corrosion rate is dependent upon temperature and species concentrations at the metal-solution interface.
Josowicz, 'A Fresh Look at Some Old Principles, The Kelvin Probe and the Nernst Equation', Anal.
See Appendix D for the derivation of the Nernst Equation. Table II The equilibrium potential (in V) of each ion across the plasma membrane and vacuolar membrane of a characean internodal cell and the plasma membrane of a squid nerve.
Figure 2 shows the potential-pH diagram is drawn using the Nernst equation. The figure shows that it is possible to synthesize cobalt particles using hydrazine because the oxidation potential of hydrazine is less noble than the reduction potential of cobalt.
The measurement reaction is based on Nernst equation:
Electrochemistry: Oxidation/reduction; anode/cathode; galvanic/electrolytic cells; half reactions; Nernst equation; electrolysis; chloralkali process; Hg, Ni/Cd, Pb batteries; electroplating.
(Note that the energies are the Gibbs energy changes for the balanced half reactions, referred to the element as arbitrary zero, and not the Gibbs energies of formation of the ions.) They are easily calculated from redox couples and where necessary the solubility products of the hydroxides using the Nernst equation and the familiar relationship: