Enthalpies of formation of 2,4,6-tribromophenol and of 2,4,6-tribromoaniline

Article abstract of DOI:10.1016/0021-9614(87)90099-1

The standard (p⁰ = 101.325 kPa) molar enthalpies of formation at 298.15 K of crystalline 2,4,6-tribromophenol and of 2,4,6-tribromoaniline were determined by both solution-reaction calorimetry and by rotating-bomb calorimetry.The values from the two methods agreed to within the limits of experimental error.The standard molar enthalpies of sublimation at 298.15 K were measured by microcalorimetry. 2,4,6-Tribromophenol: Δ_fH⁰_m(cr) = -98.5+/-2.3 kJ*mol^-1, Δ^g_crH⁰_m = 97.6+/-1.1 kJ*mol^-1; 2,4,6-tribromoaniline: Δ_fH⁰_m(cr) = 57.9+/-2.4 kJ*mol^-1, Δ^g_crH⁰_m = 101.1+/-1.1 kJ*mol^-1.The derived standard molar enthalpies of formation of the gaseous compounds were compared with values estimated assuming that each group, when substituted into the benzene ring, produces a characteristic increment in the enthalpy of formation.