Multiple Processes in Parallel

In other cases, it may not be obvious how far the reaction can proceed under a given set of conditions. Oxygen, for instance, can be reduced either to hydrogen peroxide (n = 2) or to water (n = 4), depending on the nature of the electrode, the composition and purity of the solution and the range of potential studied. There could also be a region in which both reactions occur simultaneously, and their relative rates depend on potential. In such cases, analysis of the j/K relationship could become rather complicated and extracting the mechanistic parameters may not be possible. 

Another tacit assumption is that the surface of the electrode remains unchanged during the experiment. Changes in the catalytic activity of the surface (which would change the specific rate constant of the reaction) could occur during metal deposition or dissolution, particularly when alloy deposition is concerned, where 

Physical Bectrochemistry Fundamentals, Techniques and plications. Eliezer Cileadi Copyright 2011 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31970-1 

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