Describes the relationship between the potential of an electrochemical cell at any moment in time and the standard-state cell potential Used to under-stand what happens to the potential of a voltaic cell as it comes to equilibrium
A mathematical description of electrode behavior: E is the total potential, in millivolts, developed between the sensing and reference electrodes; Ex varies with the choice of electrodes, temperature, and pressure: 2 3RT/nF is the Nernst factor (R and F are constants, n is the charge on the ion, including sign, T is the temperature in degrees Kelvin), and ai is the activity of the ion to which the electrode is responding