Thermodynamic properties of some fused chlorides

Abstract

AbstractThe stability of complexes and associates formed in compound molten electrolytes can be quantitatively estimated from the excess thermodynamic functions (free enthalpy, entropy, enthalpy). These functions can be most conveniently determined by measuring the electromotive force of chemical cells of the type where × is halogen. In this way the following systems were experimentally investigated: BeCl2–NaCl; MgCl2–LiCl; MgCl2–NaCl; MgCl2–KCl; MgCl2–RbCl; PbCl2–LiCl; PbCl2–NaCl; PbCl2–KCl; PbCl2–RbCl. The dependence of the excess partial free enthalpy on the mole fraction can be expressed by the equation where α and β are constants (for example β = 2.4 for PbCl2). In logarithmic coordinates, (ZE; (1—X1)), the experimentally determined data show a linear dependence. A curve‐linear dependence in these coordinates indicates a deviation from an ideal system. According to the magnitude of these deviations, it is possible to judge the stability of the complexes in the melts. The stability of the complexes in the melts regularly increases in the order LiCl, NaCl, KCl, RbCl.