Values of the condensed phase standard (p = 0.1 MPa) molar enthalpy of formation for 20- and 40- methylacetophenones were derived from the standard molar energies of combustion, in oxygen, at T = 298.15 K, measured by static bomb combustion calorimetry. The values of the standard molar enthalpy of vaporization, at T = 298.15 K, were measured by Calvet microcalorimetry. Combining these two values, the following enthalpies of formation in the gas phase, at T = 298.15 K, were then derived: 20-methylacetophenone, (115.7 +- 2.4) kJ mol 1, and 40-methylacetophenone, (122.6 +- 2.4) kJ mol 1. Substituent effects are discussed in terms of stability and compared with other similar compounds. The value of the standard molar enthalpy of formation for 30-methylacetophenone was estimated from isomerization schemes.
Compounds
#
Formula
Name
1
CO2
carbon dioxide
2
H2O
water
3
O2
oxygen
4
C9H10O
2-methylacetophenone
5
C9H10O
4'-methylacetophenone
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
Constraint
Phase
Method
#Points
POMD
4
Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid
Temperature, K; Liquid
Liquid
Gas
Static calorimetry
1
POMD
5
Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid
Temperature, K; Liquid
Liquid
Gas
Static calorimetry
1
RXND
4
1
2
3
Specific internal energy of reaction at constant volume, J/g
Static bomb calorimetry
1
RXND
5
1
2
3
Specific internal energy of reaction at constant volume, J/g