THERMODYNAMIC PROPERTIES OF THE NA-BI-PB SYSTEM

Thermodynamic properties of Na in an equimolar Bi-Pb alloy were determ ined at 723 K for compositions of 0.0075 less-than-or-equal-to X(Na) l ess-than-or-equal-to 0.1000 from electromotive force measurements on N a metal concentration cells with a solid Na-beta-Al2O3 electrolyte. A coulometric titration technique was used to electrochemically generate the Na metal in the Bi-Pb alloy. The results indicate that, as Na is added to Bi-Pb, the liquid becomes more associated and suggests comple x species formation with an ionic character intermediate between those observed for the constituent binaries.