Nernst Equation
The equation relating a cell's potential to the concentrations of the species involved.
Formula / equation
E = E° − (RT/nF) ln Q
Unit
V
In depth
At 298 K the coefficient simplifies to 0.0592/n when common logarithms are used. The equation shows that potential falls as products accumulate, reaching zero at equilibrium, and it is the basis of every potentiometric sensor including the pH meter.
Examples in the real world
A tenfold dilution of Cu²⁺ lowers a copper half-cell's potential by 0.0296 V.