Skip to main content
Article thumbnail
Location of Repository

Sensitivities of Key Parameters in the Preparation of Silver/Silver Chloride Electrodes Used in Harned Cell Measurements of pH

By Richard J. C. Brown, Daniela Stoica and Paul J. Brewer


A questionnaire was completed by fourteen world leading national metrology institutes to study the influence of several variables in the preparation of Ag/AgCl electrodes on the accuracy of Harned cell measurements of pH. The performance of each institute in the last decade has been assessed based on their results in eight key comparisons, organized by the Bureau International des Poids et Measures Consultative Committee for Amount of Substance, involving the measurement of pH of phosphate, phthalate, carbonate, borate and tetroxalate buffer solutions. The performance of each laboratory has been correlated to the results of the questionnaire to determine the critical parameters in the preparation of Ag/AgCl electrodes and their sensitivities with respect to the accuracy of pH measurement. This study reveals that the parameters most closely correlated to performance in comparisons are area of electrode wire exposed to the electrolyte, diameter and porosity of the Ag sphere prior to anodisation, amount of Ag converted to AgCl during anodisation, stability times employed for electrodes to reach equilibrium in solution prior to measurement, electrode rejection criteria employed and purity of reagents

Topics: pH, Harned cell, Ag/AgCl electrode, primary methods, Technology (General), T1-995, Technology, T, DOAJ:Technology (General), DOAJ:Technology and Engineering, Analytical chemistry, QD71-142, Chemistry, QD1-999, Science, Q, DOAJ:Analytical Chemistry, DOAJ:Chemistry, Chemical technology, TP1-1185
Publisher: MDPI AG
Year: 2011
DOI identifier: 10.3390/s110808072
OAI identifier:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • (external link)
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.