The platinum-20% rhodium electrode in potentiometry.
The performance of a platinum-20% rhodium alloy indicator electrode is studied in a number of potentiometric redox and acid-base titrations and compared with that of the conventional platinum electrode. The potential breaks obtained with the alloy electrode are always smaller than those obtained with the platinum electrode. The end-points are also usually indicated later than the true end-points. The bimetallic electrode system comprising platinum and platinum-rhodium electrodes gives a peak at the correct end-point even with 0.001N concentration titrations, where the ordinary potentiometric systems do not always give good results.
Athavale
V T
VT
Analytical Division, Atomic Energy Establishment, Trombay Modular Laboratories, Bombay-14, India.
Dhaneshwar
R G
RG
Sarang
D A
DA