Method and Apparatus For the Measurement of Ionic Activities in Water With Differential Pressure Transducers

摘要

The application describes an apparatus and method that gives very accurate measurements which allow one to determine the values of ionic activities of aqueous electrolyte solutions. To obtain these accurate measurements, moderately accurate measurements of vapor pressure differences between pure water (or a reference liquid) and the aqueous electrolytes is first obtained. Next, the gas in the containers and dissolved in liquids is evacuated by using a mechanical pump and the containers are immersed in a temperature controlled medium. At this point in time, the differential pressure transducer measures the difference in pressure. This reading may be used to obtain the vapor pressure of the solution and then determine corresponding ionic activities of the electrolyte in the solution.