Principles of Analytical Voltammetry

The redox current is related to the charge Q passed during the reaction by / = dQ/dt. That charge is connected to the quantity of material reacting by Faraday s law, Q = mnF, where m is the number of moles converted, F is Faraday s constant, and n is the stoichiometric number of electrons. Equating the material consumption, the flux of electrons at the electrode must be equal to the flux of the reacting species. This flux is described by Fields 1st law. Hence, the electrode current is related to the concentration of 

to describe the current for particular experimental conditions an expression is required for the concentration gradient at the electrode. Often this is obtained by first deriving an expression for c(x). If the experiment is performed in the presence of sufficient electroljfte to disregard reactant transport by migration, then the change of c(x) with time will be described wholly by Pick s 2nd law. 

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