Enthalpies of formation from the component oxides of MgWO4, CaWO4 (scheelite), SrWO4, and BaWO4, determined by high-temperature direct synthesis calorimetry

被引:22
作者
Guo, QT
Kleppa, OJ
机构
[1] UNIV CHICAGO,JAMES FRANCK INST,CHICAGO,IL 60637
[2] CHINESE ACAD SCI,INST GEOCHEM,GUIYANG 550002,GUIZHOU,PEOPLES R CHINA
关键词
alkaline-earth tungstates; enthalpy of formation; high-temperature direct synthesis calorimetry; scheelite;
D O I
10.1016/S0040-6031(96)03026-2
中图分类号
O414.1 [热力学];
学科分类号
摘要
The enthalpies of formation, from the constituent oxides, of tungstates of alkaline earth metals, MeWO(4)(Me is Mg, Ca, Sr, Ba), have been determined by direct synthesis calorimetry at 1473 +/- 2 K. The following values of Delta H-f at 298 K (kJ mol(-1)) are reported: MgWO4, -73.9 +/- 4.8; CaWO4 (scheelite), -168.5 +/- 3.3; SrWO4, -2179 +/- 3.6; BaWO4, -256.2 +/- 3.9. The results are compared with data available in the literature.
引用
收藏
页码:53 / 61
页数:9
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