ISSN:
1089-7690
Quelle:
AIP Digital Archive
Thema:
Physik
,
Chemie und Pharmazie
Notizen:
Effusion cell beams containing the gaseous species HPO, HPO2, HPO3, and POBr along with other products were generated by the reaction of H2O(g) or Br2(g) with Ca2P2O7(s). The species were identified by mass spectrometry, and were characterized thermochemically from the study of several reaction equilibria. Reaction enthalpies and standard enthalpies of formation were derived from third law analysis of the equilibrium data, yielding the ΔfH°298 values HPO, −34.2; HPO2, −110.6; HPO3, −168.8; and POBr, −53.5, all in kcal mol−1. Our new result for POBr is in serious disagreement with a value reported in the literature; there are no previous reports on the other species studied here. A preliminary ΔfH°298 value of −60.2 kcal mol−1 was also obtained for POCl(g), this time in reasonable accord with a literature value. The new thermochemical data yield calculated compositions in agreement with measured values for some lamp gas mixtures.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.466782
Permalink