Thermodynamics of dilute solution of Gd in Bi

Abstract

The thermodynamics of dilute solution of Gd in Bi were determined by means of the electromotive force (EMF) measurement method using a cell consisting of molten chloride and liquid bismuth in temperature range from 775 to 1055 K, with the Gd molar fraction range from about 10 –5 to 10 –3 . Gd concentration has less effect on the activity coefficient. A considerable increase of the activity coefficient on the temperature was observed. The heat of formation of liquid Gd–Bi alloys was deduced from the measured activity coefficient. There is a linear dependence of experimental ΔHMGd–Bi on the Gd concentration. The experimental results of ΔHMGd–Bi were compared with the values predicted by Miedema's model.