The lead amalgam/lead sulfate electrode redesigned and reassessed

To make the (Pb)Hg‖PbSO₄‖SO ₄ ²⁻ electrode really usable and attractive for extensive application to thermodynamic studies, a new, simplified design and a convenient preparative procedure have been introduced, ensuring stable amalgams and reproducible electrode potentials. The electrode so prepared has been exhaustively characterized both thermodynamically and as a SO ₄ ²⁻ -sensing electrode, in different sulfate solutions, including H₂SO₄. The past discrepancies of standard potentials-mainly due to preparation and/or handling problems-are discussed and, for a final resolution of the question, a practical standardization procedure is proposed.