ABSTRACT

A rotating-bomb combustion calorimeter was used to determine the standard (p = 0.1 MPa) molar enthalpies of combustion, DcH m, of the liquids 2-acetyl-3-methylthiophene, 2-acetyl-4-methylthiophene, and 2-acetyl-5-methylthiophene, from which the standard molar enthalpies of formation, DfH m, in the liquid phase, at the temperature of 298.15 K, were derived. The standard molar enthalpies of vaporization, Dg l H m, at T = 298.15 K, for those compounds, were obtained by high temperature Calvet microcalorimetry. From the experimental results, the standard molar enthalpies of formation of the three methyl substituted 2-acetylthiophene isomers, in the gaseous phase, were calculated and a comparison between the relative stability and the energetic of the three isomers was carried out.

Compounds

#	Formula	Name
1	H2O4S	sulfuric acid
2	CO2	carbon dioxide
3	H2O	water
4	O2	oxygen
5	C7H8OS	2-acetyl-3-methylthiophene
6	C7H8OS	2-acetyl-4-methylthiophene
7	C7H8OS	2-acetyl-5-methylthiophene

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Phase	Method	#Points
POMD	5	Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid	Temperature, K; Liquid	Liquid Gas	Vacuum sublimation drop method	1
POMD	5	Molar enthalpy, kJ/mol ; Gas	Temperature, K; Gas Pressure, kPa; Gas	Gas	vacuum microcalorimetry	1
POMD	6	Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid	Temperature, K; Liquid	Liquid Gas	Flow calorimetry	1
POMD	6	Molar enthalpy, kJ/mol ; Gas	Temperature, K; Gas Pressure, kPa; Gas	Gas	vacuum microcalorimetry	1
POMD	7	Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid	Temperature, K; Liquid	Liquid Gas	Flow calorimetry	1
POMD	7	Molar enthalpy, kJ/mol ; Gas	Temperature, K; Gas Pressure, kPa; Gas	Gas	vacuum microcalorimetry	1
RXND	1 5 2 3 4	Specific internal energy of reaction at constant volume, J/g			Rotating bomb calorimetry	1
RXND	1 6 2 3 4	Specific internal energy of reaction at constant volume, J/g			Rotating bomb calorimetry	1
RXND	1 7 2 3 4	Specific internal energy of reaction at constant volume, J/g			Rotating bomb calorimetry	1

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Experimental thermochemical study of the three methyl substituted 2-acetylthiophene isomers

Ribeiro da Silva, M. A. V.[Manuel A. V.], Santos, A. F. L. O. M.[Ana Filipa L.O.M.]

ABSTRACT