Article

Thermochemical properties of two benzimidazole derivatives: 2-Phenyl- and 2-benzylbenzimidazole

Department of Chemistry, University of Porto, Oporto, Porto, Portugal
The Journal of Chemical Thermodynamics (Impact Factor: 2.42). 11/2005; 37(11):1168-1176. DOI: 10.1016/j.jct.2005.02.008

ABSTRACT The standard (p∘ = 0.1 MPa) molar enthalpy of formation for gaseous 2-phenylbenzimidazole (2-PhBIM) and 2-benzylbenzimidazole (2-BzBIM) were derived from the standard molar enthalpies of combustion, at T = 298.15 K, measured by static bomb calorimetry, and the standard molar enthalpy of sublimation, at T = 298.15 K, measured by Calvet microcalorimetry in the case of 2-phenylbenzimidazole or derived from the variation of the vapour pressures, determined by the Knudsen effusion technique, with temperatures between (393 and 412) K for 2-benzylbenzimidazole. Heat capacities, in the temperature ranges from (268.15 to 322.10) K for 2-phenylbenzimidazole and (270.15 to 316.02) K for 2-benzylbenzimidazole, were also measured with a differential scanning calorimeter. View Within Article

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