Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Saturation molalities and standard molar enthalpies of solution of a-D-xylose(cr) in H2O(l); standard molar enthalpies of solution of 1,4-b-D-xylobiose(am), and 1,4-b-D-xylotriose(am) in H2O(l)

Goldberg, R. N.[Robert N.], Lang, B. E.[Brian E.], Coxon, B.[Bruce], Decker, S. R.[Stephen R.]
J. Chem. Thermodyn. 2012, 52, 2-10
ABSTRACT
The saturation molality of a-D-xylose(cr) in water was measured by using HPLC and is m(sat) = (8.43 +- 0.42) mol kg 1 at T = 298.15 K. It was also established that the anhydrous form of a- D-xylose(cr) is the crystalline form that is in equilibrium with the aqueous solution at T = 298.15 K. Solution calorimetry was used to measure the following standard molar enthalpies of solution at T = 298.15 K: DsolH m = (12.10 +- 0.12) kJ mol 1 for a-D-xylose(cr); DsolH m = (8.1 +- 2.7) kJ mol 1 for 1,4-b-D-xylobiose(am); and DsolH m = (24.1 +- 6.4) kJ mol 1 for 1,4-b-D-xylotriose(am). It was observed that both 1,4-b-D-xylobiose(am) and 1,4-b-D-xylotriose(am) were amorphous substances and that they form thick gels in water in which no solid phase is present. Consequently, it is not possible to measure m(sat) for these two substances. All substances were carefully characterized by using both HPLC and Karl Fischer analysis. NMR was used to measure the anomeric purity of the a-D-xylose(cr). Thermodynamic network calculations were used to calculate standard molar formation properties for the aforementioned substances.
Compounds
# Formula Name
1 H2O water
2 C5H10O5 D-xylose
3 C10H18O9 1,4-.beta.-xylobiose
4 C15H26O13 1,4-.beta.-D-xylotriose
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
  • 2
  • 1
  • Molality, mol/kg ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Crystal - 2
  • HPLC
  • 1
  • POMD
  • 2
  • 1
  • Molar enthalpy of solution, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 2; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Calvet calorimetry
  • 13
  • POMD
  • 3
  • 1
  • Molar enthalpy of solution, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 3; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Calvet calorimetry
  • 5
  • POMD
  • 1
  • 4
  • Molar enthalpy of solution, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 4; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Calvet calorimetry
  • 5