Thermodynamics Research Center / ThermoML | Thermochimica Acta

THE STANDARD ENTHALPIES OF FORMATION OF L-ASPARAGINE AND L-a- GLUTAMINE

Contineanu, I.[Iulia], Neacsu, A.[Ana], Perisanu, S.[Stefan]
Thermochim. Acta 2010, 497, 1-2, 96-100
ABSTRACT
The energies of combustion of L-asparagine and L-a-glutamine were measured in a static bomb adiabatic calorimeter. Corrections were made for the heats due to the ignition of sample and for the nitric acid formation. The derived enthalpies of formation in solid state of asparagine monohydrate, nonhydrated asparagine and glutamine are respectively -1084.1 +- 3.0 , -788.1 +- 4.7 and -834.3 +- 4.6 kJ mol-1. The data of enthalpy of formation are compared with literature values and with estimated values by means of group additivity, using parameters recommended by Domalski and Hearing. The discrepancies between experimental and calculated values are explained by considering the number and strength of intermolecular hydrogen bonds. The dehydration of asparagine monohydrate and the possible melting of the three amino acids were investigated by means of DSC. Glutamine melts without considerable decomposition at about 182deg C, while asparagines decompose during the fusion process (208deg C).
Compounds
# Formula Name
1 CO2 carbon dioxide
2 N2 nitrogen
3 H2O water
4 O2 oxygen
5 C4H8N2O3 L-asparagine
6 C4H10N2O4 L-asparagine monohydrate
7 C5H10N2O3 L-glutamine
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
  • 5
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Crystal
  • Liquid
  • Gas
  • DSC
  • 1
  • POMD
  • 5
  • Normal melting temperature, K ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • POMD
  • 7
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Crystal
  • Liquid
  • Gas
  • DSC
  • 1
  • POMD
  • 7
  • Normal melting temperature, K ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • RXND
  • 5
  • 1
  • 2
  • 3
  • 4
  • Molar internal energy of reaction at constant volume, kJ/mol
  • Static bomb calorimetry
  • 1
  • RXND
  • 6
  • 1
  • 2
  • 3
  • 4
  • Molar internal energy of reaction at constant volume, kJ/mol
  • Static bomb calorimetry
  • 1
  • RXND
  • 7
  • 1
  • 2
  • 3
  • 4
  • Molar internal energy of reaction at constant volume, kJ/mol
  • Static bomb calorimetry
  • 1