Cell Assembly:

The cell assembly consists of a platinum gauze working electrode platinum wire counter electrode and a saturated calomel electrode as the reference electrode. The counter electrode is divided from the test solution through a porous tube holding the similar supporting electrolyte.

Figure: Electrolysis cells for poentionstatic coulometry: Working electrode: a) Platinum gauze (b) Mercury pool

Sometimes a mercury cathode is used in the alteration of a platinum gauze electrode that was display in the above figure. This cathode is meaningful for separating the simply reducible elements during an analysis. For example, copper, cobalt, nickel, silver and cadmium are simply separated from ions like as aluminium, titanium, alkali phosphates and metals. The precipitated elements dissolve within mercury and form amalgams.