Enthalpies of vaporization of some β-diketones
Abstract
Molar enthalpies of vaporization of six β-diketones have been measured at 298·15 K by a direct calorimetric method; for 1,1,1,5,5,5-hexafluoropentane-2,4-dione, ΔHv0= 7·31 ± 0·03 kcal mol–1, 1,1,1-trifluoropentane-2,4-dione, 8·90 ± 0·4, 2,6-dimethylheptane-3,5-dione, 13·40 ± 0·04, 2,2-dimethylheptane-3,5-dione, 13·59 ± 0·03, 2,2,6-trimethylheptane-3,5-dione, 13·80 ± 0·05, and for 2,2,6,6-tetramethylheptane-3,5-dione, ΔHv0= 14·23 ± 0·03 kcal mol–1. The relationship between the enthalpy of vaporization and the normal boiling point is briefly discussed.