Thermodynamics Research Center / ThermoML | Thermochimica Acta

Low temperature heat capacities and standard molar enthalpy of formation of sodium benzoate C6H5COONa (s)

Kong, Y.-X.[Yu-Xia], Di, Y.-Y.[You-Ying], Qi, Y.-D.[Yu-Dong], Yang, W.-W.[Wei-Wei], Tan, Z.-C.[Zhi-Cheng]
Thermochim. Acta 2009, 488, 1-2, 27-32
ABSTRACT
Sodium benzoate was synthesized by the method of liquid phase synthesis, in which benzoic acid and anhydrous sodium carbonate were chosen as the reactants. The structure and composition of the compound were characterized by FTIR, chemical analysis, elemental analysis and X-ray powder diffraction techniques. Low temperature heat capacities of the compound were measured by a precision automated adiabatic calorimeter over the temperature range from 78 to 400 K. A polynomial equation of the heat capacities as a function of the temperature was fitted by least square method. The smoothed heat capacities and the thermodynamic functions of the compound relative to 298.15K have been calculated based on the equation. In accordance with Hess law, the standard molar enthalpy of formation of the title compound C6H5COONa (s) was determined to be fH.m[C6H5COONa, s] = .(642.56 } 0.64) kJmol.1 by using an isoperibol solution-reaction calorimeter.
Compounds
# Formula Name
1 Na sodium
2 C graphite
3 H2 hydrogen
4 O2 oxygen
5 C2H4O2 acetic acid
6 C7H6O2 benzoic acid
7 C2H3NaO2 sodium ethanoate
8 C7H5NaO2 sodium benzoate
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
  • 8
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Vacuum adiabatic calorimetry
  • 106
  • RXND
  • 8
  • 1
  • 2
  • 3
  • 4
  • Molar enthalpy of reaction, kJ/mol
  • Static bomb calorimetry
  • 1
  • RXND
  • 5
  • 6
  • 7
  • 8
  • Molar enthalpy of reaction, kJ/mol
  • Solution calorimetry
  • 1