The titration proceeds at a constant electric current (constant current coulometry). OH- ions
(that are produced according to reaction (1)) diffuse rapidly into the solution and reacts with
H+ ions arising from the sample. The amount of HCl (nHCl , in mole) is the same as the
amount of OH- produced by electrolysis. This one (nOH) results from the lows of electrolysis
(Faraday) applied to reaction (1):