Bulk electrolysis methods current efficiency

Bulk electrolysis methods are also classified according to purpose. For example, one form of analysis involves determination of the weight of a deposit on the electrode (electrogravimetry). In this case 100% current efficiency is not required, but the substance of interest must be deposited in a pure, known form. In coulometry, the total quantity of electricity required to carry out an exhaustive electrolysis is determined. The quantity of material or number of electrons involved in the electrode reaction can then be determined by Faraday s laws, if the reaction occurred with 100% current efficiency. For electroseparations, electrolysis is used to remove, selectively, constituents from the solution. 

Electrolysis at controlled potential is the most efficient method of carrying out a bulk electrolysis, because the current is always maintained at the maximum value (for given cell conditions) consistent with 100% current efficiency. Note that the rate of electrolysis is independent of Cq(0), so that electrolysis of a 0.1 M solution of O and a 10 M solution of O should require the same amount of time, given the same values of E, A, V, and thq. 

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