Alkali Metal-Alkali Halide Solutions: Thermodynamics of the K-KCl System.

In order to obtain thermodynamic in formation on mixtures constituted with alkali metals and their halides, we investigated the K-KCl system by vapor pressure measurements. The method chosen uses the features of both the Rodebush-Dixon and ebullition methods. The apparatus, consistent with the experimental requirements of such a system, allows one to investigate a wide temperature and pressure range. The determination of the vapor pressure of potassium between 970 and 1140 K was a check on the operation of the apparatus. Vapor pressure measurements above the K-KCl liquid bath between 970 K and 1140 K yielded the activity of potassium at X K = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 and 0.9.