Anodic dissolution of the mercury electrode by the CH3O− ions formed during the reduction of organic compounds in methanol

Anodic dissolution of the HMDE from CH₃O^? ions formed during the electrochemical reduction of organic compounds in methanol arises only if the electroreduction is non-reversible. When, however, the organic substances undergo a reversible reduction, the CH₃O^? ions formed during the reduction are neutralized by the protons released during reoxidation. The anodic dissolution of the mercury electrode is attributed to the formation of insoluble Hg₂(OCH₃)₂, as with many other ions which depolarize the mercury electrode in aqueous solution with the formation of insoluble salts.