Performance Characteristics of Cells Containing Two Potentiometric Sensors: Application to a Cell Containing Hydralazinium and Chloride Electrodes

Conventional plastic membrane electrode, selective to hydralazinium cation (Hz) was constructed by incorporation of Hz-phosphotungstate ion associate in a poly(vinyl chloride) membrane. The influence of membrane composition, pH of the test solution and foreign ions on the cell performance was investigated. This was compared to the corresponding influence on a cell constructed by replacing the reference electrode in the conventional cell with Cl-selective electrode. The results indicated that the first cell showed Nernstian behavior, while the latter exhibited super Nernstian response. The selectivity for both cases was high. However the working pH range was narrower in case of the cell with two sensors.