Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The standard (p = 0.1 MPa) molar enthalpies of combustion for the 3- and 4-nitrobenzophenones and for the 3,30-dinitrobenzophenone, in the crystalline state, were determined, at the temperature T = 298.15 K, using a static bomb combustion calorimeter. For these compounds, the standard molar enthalpies of sublimation at T = 298.15 K, were determined by Calvet microcalorimetry. For the 3- and 4-nitrobenzophenones the vapour pressures as function of temperature were measured by the Knudsen effusion technique and the standard molar enthalpies of sublimation at T = 298.15 K, were derived by the Clausius-Clapeyron equation. These values were used to derive the standard molar enthalpies of formation of the compounds in their condensed and gaseous phases, respectively. For 3- and 4-nitrobenzophenones, the standard (p = 0.1 MPa) molar enthalpies, entropies and Gibbs functions of sublimation, at T = 298.15 K, were derived. The derived standard molar enthalpies of formation in the gaseous state are analysed in terms of structural enthalpic increments.