Resumen de Zinc Electrodes and the Thermodynamics of a Galvanic Cell

Donald A. Probst, Giles Henderson

• Although zinc is commonly employed as an electrode in laboratory studies of galvanic cells, we find that under ambient conditions, this electrode may be poisoned by a surface coating on zinc hydroxide. The formation of a strongly adhering, non conducting surface film impedes current flow and causes measured cell potentials to ramp downward with time. Thermodynamic calculations and laboratory experiments confirm that this difficulty can be completely eliminated by buffering the anode electrolyte at pH = 4.0.