Effect of some chelating ligands on the potential response of the chalcocite copper ion-selective electrode

The effects of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, aminoacetic acid, iminodiacetic acid, nitrilotriacetic acid, ethylenediaminediaminetetraacetic acid, diethylenetriaminepentaacetic acid and triethylenetetraminehexaacetic acid on the behaviour of the synthetic chalcocite (copper(I) sulphide) copper-selective electrode are described. The effects of those ligands on the electrode response at different pH values is explained on the assumption that copper(I) ions contribute to the potential indicated. Copper(I) ions originate from the membrane phase and participate in exchange and redox reactions. The effects of oxygen and temperature are reported. The electrode response can be predicted on the basis of copper(II) equilibria in solution, only if the conditions are such that there is no interference from copper(I) ions.