ABSTRACT

The standard (p = 0.1 MPa) molar enthalpies of formation of crystalline 2-thiophenecarboxamide and 2-thiopheneacetamide were calculated from the standard molar energies of combustion, in oxygen, to yield CO2(g), N2(g) and H2SO4 Ae 115 H2O(aq), measured by rotating-bomb combustion calorimetry, at T = 298.15 K. The vapour pressures of these two compounds were measured as functions of temperature by Knudsen-effusion mass loss technique; from the Clausius Clapeyron equation the standard molar enthalpies of sublimation, at T = 298.15 K, were derived. The results were as follows... From these values, the standard molar enthalpies of formation of both compounds in their gaseous phase were derived and interpreted in terms of enthalpic increments and molecular structure.

Compounds

#	Formula	Name
1	H2O4S	sulfuric acid
2	CO2	carbon dioxide
3	N2	nitrogen
4	H2O	water
5	O2	oxygen
6	C5H5NOS	2-thienylamide
7	C6H7NOS	2-thiopheneacetamide

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	6	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal Pressure, kPa; Crystal	Crystal	estimated by mass and dimensions of pellet of crystal	1
POMD	6	Vapor or sublimation pressure, kPa ; Crystal	Temperature, K; Crystal	Crystal Gas	Calculated from knudsen effusion weight loss	36
POMD	7	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal Pressure, kPa; Crystal	Crystal	estimated by mass and dimensions of pellet of crystal	1
POMD	7	Vapor or sublimation pressure, kPa ; Crystal	Temperature, K; Crystal	Crystal Gas	Calculated from knudsen effusion weight loss	36
RXND	6 1 2 3 4 5	Specific internal energy of reaction at constant volume, J/g			Rotating bomb calorimetry	1
RXND	7 1 2 3 4 5	Specific internal energy of reaction at constant volume, J/g			Rotating bomb calorimetry	1

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Standard molar enthalpies of formation and of sublimation of 2-thiophenecarboxamide and 2-thiopheneacetamide

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

ABSTRACT