Vapor pressure measurements of lanthanum-bismuth alloys by mass-spectrometric method

Citation
Y. Shoji et al., Vapor pressure measurements of lanthanum-bismuth alloys by mass-spectrometric method, INT J THERM, 21(2), 2000, pp. 585-591
Citations number
13
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
INTERNATIONAL JOURNAL OF THERMOPHYSICS
ISSN journal
0195-928X → ACNP
Volume
21
Issue
2
Year of publication
2000
Pages
585 - 591
Database
ISI
SICI code
0195-928X(200003)21:2<585:VPMOLA>2.0.ZU;2-H
Abstract
Vapor pressures of Bi-2 (g) over La0.03Bi0.97 and two-phase mixtures of Bi + LaBi2. LaBi2 + LaBi, LaBi + La4Bi3, La4Bi3 + La5Bi3, and La5Bi3 + La2Bi w ere measured in the temperature range from 795 to 1066 K with a time-of-fli ght mass spectrometer equipped with a tungsten Knudsen cell. The vapor pres sure of Bi-2 (g) over the two-phase mixtures of La2Bi + La could not be det ected experimentally in this temperature range. The thermodynamic activity of bismuth was determined from the vapor pressure of Bi-2 (g). Thermodynami c activities of lanthanum over alloys were derived from those of bismuth in the alloys in this study and that of lanthanum in the bismuth in a previou s study by graphic integration of the Gibbs-Duhem equation. Thermodynamic q uantities such as Gibbs Free energy of formation, excess enthalpy, etc., we re also calculated from the thermodynamic activities.