Monomolecular preceding CE and consecutive EC reactions

The classical example is the reduction of formaldehyde [149], which exists in solution in equilibrium with its hydrated form, methyleneglycol. The latter species dominates in the equilibrium situation, but is not electroactive. So the preceding reaction is dehydration of the methylenegly c ol. 

One may think of the reduction of an organic substance to a less-stable product which is subsequently protonated or rearranged to form a non-oxidizable species B [21, 22], or the formation of metallic compounds in the mercury phase. 

In the literature, some authors refer the EC scheme to the trivial case where the RP, RE scheme given before applies, but the electrode reaction is studied by considering a net oxidation. Here, we disregard this definition. 

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