FORMATION AND PROPERTIES OF MIXED CADMIUM SULFIDE-SILVER SULFIDE, AND MIXED MERCURY SULFIDE-SILVER SULFIDE MEMBRANES FOR ELECTRODES SELECTIVE TO CADMIUM(II) AND MERCURY(II)

The preparation and behavior of cadmium(II)-selective and mercury (II)-selective electrodes made from mixed metal sulfide-silver sulfide precipitates are discussed. The performance of the cadmium-selective electrode is satisfactory in accordance with similar electrodes described in the literature. Responses to cadmium(II), alone as well as in the presence of complexing agents such as EDTA, NTA, trien and tetren, were determined as a function of pH. Selectivity coefficients are presented. The mercury(II)-selective electrodes generally did not behave reproducibly; at best, the limit of detection was about 10-5 M. © 1979.