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 equation

Etymology: Hermann W. Nernst, German physicist, 1864-1941; L, aequare, to make equal
an expression of the relationship between the electrical potential across a membrane and the ratio between the concentrations of a given species of permeant ion on either side of the membrane.

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.

Nernst equation

gives the amplitude and sign of the electronic potential created when a semipermeable membrane separates charged ions.
References in periodicals archive ?
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.
Substituting (6) into (1) and (2), the Nernst equation for V-RFB becomes
0), the model matched the experimental cell potential at equilibrium but the predicted curve swings 5 % off the experimental curve in the middle of charging the V-RFB; this is the effect of the logarithmic function (Log10) in the Nernst equation.
Applying the Nernst equation, the electrode potential for the cathodic half reaction can be written as follow,
See Appendix D for the derivation of the Nernst Equation.
The equilibrium potentials for each ion across the plasma membrane and the vacuolar membrane calculated from the Nernst Equation (at 298 K) are given in Table II.
Cl], the Goldman-Hodgkin-Katz Equation reduces to the Nernst Equation for [K.
They are easily calculated from redox couples and where necessary the solubility products of the hydroxides using the Nernst equation and the familiar relationship: