Thermodynamic properties of molten Na‐Te solutions

Abstract Thermodynamic properties of liquid Na‐Te solutions were measured over the range 0–52 at.% Na at temperatures between 573 and 873 K by means of alloy concentration cells. Beta alumina was used as the solid electrolyte. The following properties were derived from the emf data: Δ G , Δ H , Δ S , the excess heat capacity C E p and the excess stability, ES. The Gibbs energy, enthalpy and entropy showed marked negative deviations. The plot of excess stability versus composition exhibits a rather flat shoulder between 10 and 20 at.% Na and a broad maximum or shoulder near 50% Na indicating maximum short‐range ordering near these compositions. Liquidus and invariant points on the phase diagram as well as the Gibbs energies of formation of the solid compounds NaTe 3 , NaTe and Na 2 Te have also been determined.