. . . . . . "e not excluded.The concentration of the inert electrolyte will conveniently be from 0.1 M to saturation, preferably from 0.3 M to 0.5 M and more preferably 0.4 M.Examples of inert electrolyte materials are ammonium, quaternary ammonium and alkali and alkaline earth metal salts e.g. lithium potassium, sodium and magnesium." .