Sur la détermination générale de l'impédance de concentration (diffusion convective et réaction chimique) pour une électrode à disque tournant

A general relation is demonstrated between the concentration impedance in the presence of a homogeneous chemical reaction and the impedance due to convective diffusion. This relation is specified for the case where the diffusion coefficients of the substances involved in the reaction are equal. It can be used to treat experimental results if the impedance of convective diffusion can be obtained in an analytical form. Three approximation formulas for this relation are given, valid respectively for low, medium, and high values of the module of a dimensionless complex variable which is a function of the frequency and the rate constants. Examples are given of numerical applications of these formulas for predicting the value of the concentration impedance, given the frequency, the Schmidt number, the rate constants of the reaction, and the disc rotation rate.