A Novel Use of Electrode Sensitivity for Ion-Selective Electrodes in Determining the Amounts of Water in Nonaqueous Systems

Electrode sensitivity (ES), the change in cell potential for a given change in water concentration using proton-isoconcentration technique (PICT), remains constant under comparable experimental conditions. This permits a direct potentiometry of water by single dilution in a sample of water-organic solvent mixture using a micro pH-glass and ordinary reference electrodes or two ion-selective electrodes (i.e. a micro pH-glass electrodes and Radiometer Chloride Selectrode). The method is simple, rapid and accurate compared with the use of calibration graphs. Results obtained on selected important solvents demonstrate a satisfactory performance of ES using PICT