13595-30-7Relevant articles and documents
The vapor pressures of vanadium(II) chloride, vanadium(III) chloride, vanadium(II) bromide, and vanadium(III) bromide by Knudsen effusion
Mccarley, Robert E.,Roddy, James W.
, p. 60 - 63 (1964)
The vapor pressures of crystalline VCl2, VBr2, VCl3, and VBr3 have been measured by the Knudsen effusion method. Only the simple vaporization was observed for VCl2 and VBr2 over the interva
Vaporization reactions of vanadium(III) bromide. Dissociation and disproportionation equilibria, and the formation of vanadium(IV) bromide
Mccarley, Robert E.,Roddy, James W.
, p. 54 - 59 (2008/10/08)
The equilibria VBr3(s) = VBr2(s) + 1/2Br2(g) (1) and 2VBr3(s) = VBr2(s) + VBr4(g) (2) were studied over the range 644 to 805°K. by transpiration in helium. For (1) ΔH° = 23.1 ± 0.9 kcal./mole and ΔS° = 10.6 ± 0.4 e.u., while for (2) ΔH° = 37.7 ± 1.3 kcal./mole and ΔS° = 34.7 ± 1.2 e.u. Both transpiration in bromine vapor and static pressure measurements using a glass diaphragm gage showed that VBr3(s) vaporized as VBr4(g) in the presence of bromine according to VBr3(s) + 1/2Br2(g) = VBr4(g) (3). The transpiration measurements gave for (3) ΔF° = 15.80 × 103 - 23.9T for T = 515-585°K. Solid VBr4 was isolated by condensation of the vapor at -78° and was found to be stable at -45°. At higher temperatures the solid decomposed to VBr3(s) and bromine.
