Procedures for testing ph responsive glass electrodes at 25, 37, 65 and 85 °c and determination of alkaline errors up to 1 moldm-3 na+, k+, li+

Abstract

over the pH range 0-14 at 25 °C in the absence of alkali metal ions, in the presence of Na+, K+, Li+ at high pH, and extended to 37 °c for clinical usage and to higher temperatures (65, 85 °c). The method is based on indirect comparison with results for hydrogen gas electrodes but uses silver—silver chloride reference electrodes in cells without liquid junction. With specially developed chloride-containing test buffers, it is now possible to determine the errors of glass electrodes with an accuracy of + 1.2 mV (+ 0.02 pH) over the normal pH range at 25, 65 and 85 °c and to measure Na+, K+, Li+ errors at up to 1 mol dm-3 cation at constant pH for pH >6.5 at 25 °c. Examples are given from results of testing commercial electrodes. A new method has been developed for testing glass electrodes. © 1985, Walter de Gruyter. All rights reserved.