How to define the potential difference driving net chemical transformation

Abstract

Purely kinetic (as opposed to thermodynamic) considerations allow the derivation of a ‘kinetic potential difference’ from the instantaneous composition of chemically reacting systems. The net rate of multistep multi-reactant chemical transformations is proportional to this potential difference. The proportionality constant is given by the equilibrium exchange velocity. The rate vs. potential difference plot is linear, and linearity is not limited to small deviations from chemical equilibrium. The new (kinetic) definition appears to compare favourably with the conventional (‘thermodynamic’) one, including usefulness in the computation of instantaneous reaction rates, application of network theory, and consistency with the classical thermodynamic concept of chemical potential.