Mass Spectrometric Study of Gaseous Molybdenum, Tungsten, and Uranium Oxides

摘要

Partial pressures of the gaseous oxides MoO, MoO2, MoO3, WO, WO2, WO3, UO, UO2, and UO3in the systems Mosngbnd;Al2O3and Usngbnd;Al2O3have been measured by mass spectrometric methods. The vapor pressure of uranium has also been determined. The reaction enthalpies derived from these measurements are:Reactionthinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;Dgr;H0ogr;thinsp;kcal/moleMoOlpar;grpar;rarr;Molpar;grpar;plus;Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;116plusmn;15MoO2lpar;grpar;rarr;Molpar;grpar;plus;2Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;262plusmn;10MoO3lpar;grpar;rarr;Molpar;grpar;plus;3Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;411plusmn;7WOlpar;grpar;rarr;Wlpar;grpar;plus;Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;154plusmn;10WO2lpar;grpar;rarr;Wlpar;grpar;plus;2Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;296plusmn;7WO3lpar;grpar;rarr;Wlpar;grpar;plus;3Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;443plusmn;7UOlpar;grpar;rarr;Ulpar;grpar;plus;Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;179plusmn;7UO2lpar;grpar;rarr;Ulpar;grpar;plus;2Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;340plusmn;7UO3lpar;grpar;rarr;Ulpar;grpar;plus;3Olpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;493plusmn;7Ulpar;srpar;rarr;Ulpar;grpar;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;thinsp;126plusmn;5.