Faradaic homogeneous chemical reaction

The charge is a valuable magnitude for identifying the presence of homogeneous chemical reactions or, in general, deviations from a pure faradaic behavior. Thus, in absence of adsorption of redox species, the normalized charge-time curves can be written as... 

The two major classes of voltammetric technique 4 Evaluation of reaction mechanisms 6 General concepts of voltammetry 6 Electrodes roles and experimental considerations 8 The overall electrochemical cell experimental considerations 12 Presentation of voltammetric data 14 Faradaic and non-Faradaic currents 15 Electrode processes 17 Electron transfer 22 Homogeneous chemical kinetics 22 Electrochemical and chemical reversibility 25 Cyclic voltammetry 27 A basic description 27 Simple electron-transfer processes 29 Mechanistic examples 35... 

Rate of reactions at the electrode surfaces depends on mass transfer, which mainly influences the current 1. The simplest electrode reactions are those in which the rates of all associated chemical reactions are very rapid compared to those of the mass transfer processes. If an electrode process involves only fast heterogeneous charge transfer and mobile, reversible homogeneous reactions, it implies that (1) the homogeneous reactions are at equilibrium and (2) the surface concentrations of species involved in the faradaic process are related to the electrode potential. The net rate of the electrode reaction, Vrxn, is then governed totally by the rate at which the electroactive species is brought to the surface by mass transfer, v f The reaction rate can be expressed as ... 

A preliminary electrochemical overview of the redox aptitude of a species can easily be obtained by varying with time the potential applied to an electrode immersed in a solution of the species under study and recording the relevant current-potential curves. These curves first reveal the potential at which redox processes occur. In addition, the size of the currents generated by the relative faradaic processes is normally proportional to the concentration of the active species. Finally, the shape of the response as a function of the potential scan rate allows one to determine whether there are chemical complications (adsorption or homogeneous reactions) which accompany the electron transfer processes. 

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