Ion concentration measurement in liquid - is performed by comparison with reference liquid of variable ion concentration to achieve wide range

摘要

A method is used for measuring the concentration of ions of interest in a liquid. The potential difference is measured between two similar electrodes sensitive to the ions of interest, and in connection throught a diaphragm. One of the electrodes is immersed in the solution under test and the other is immersed in a reference liquid. To extend the range of measurement, the second liquid can be varied by known amounts in its concentration in the ions of interest. The test cell (9) contains two glass electrodes (11) and is fed with the solution under test through two valves (18, 19).