Thermodynamic properties of liquid (indium+bismuth)

Abstract

Partial molar thermodynamic functions of In and Bi in { xIn + (1 − x)Bi}(l) and integral excess thermodynamic functions for the range of 673 to 873 K were determined by measuring the e.m.f. of the concentration cells: In(1)∥{0.01InBr+0.99(0.60 LiBr + 0.40 KBr)}(1)∥{xIn+(1+x)Bi}(1) Thermodynamic functions were estimated for 12 values of x from 0.05 to 0.90 and compared with the results obtained by other authors. Negative deviations of In and Bi activities from Raoult's law and negative values of excess Gibbs energies and enthalpies indicate a mutual interaction of both components in the alloys. Interactions between In and Bi are compatible with the presence in the solid phase of the three intermetallic compounds: InBi, In 5Bi 3, and In 2 Bi. The curves of excess enthalpy and excess Gibbs energy are asymmetric; more negative values of these functions appear for x > 0.5, i.e. in the range where intermetallic compounds occur. The excess entropies are low and positive and for x ⪡ 0.5 they do not exceed the experimental error.