Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Studies on the interactions of diglycine and triglycine with polyethylene glycol 400 in aqueous solutions by density and ultrasound speed measurements

Sahin, M.[Melike], Ayranci, E.[Erol]
J. Chem. Thermodyn. 2013, 58, 70-82
ABSTRACT
Density and ultrasound speed were measured accurately for diglycine + water, triglycine + water, diglycine + water-polyethylene glycol 400 (PEG400) and triglycine + water-PEG400 solutions at T = (293.15, 298.15, 303.15 and 308.15) K. The results were used in evaluating thermodynamic properties as apparent molar volumes (VO) and apparent molar isentropic compressions (KSU) of diglycine and triglycine in water and in PEG400 solutions. Infinite dilution values of these parameters, Vo O, and Ko SU, were obtained from their plots as a function of molality by extrapolation and have been utilized in obtaining transfer volumes and transfer compressions at infinite dilution. All transfer volumes and transfer compressions were found to increase with increasing molality of PEG400. Apparent molar isobaric expansions were derived from the temperature dependence of VO values at infinite dilution and at finite concentrations. All the results were interpreted in terms of solute (diglycine or triglycine) and co-solute (PEG400) and solvent (H2O) interactions
Compounds
# Formula Name
1 C4H8N2O3 glycylglycine
2 C6H11N3O4 glycylglycylglycine
3 H2O water
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
  • 1
  • 3
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 1; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Vibrating tube method
  • 40
  • POMD
  • 1
  • 3
  • Speed of sound, m/s ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 1; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Sing-around technique in a fixed-path interferometer
  • 40
  • POMD
  • 2
  • 3
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 2; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Vibrating tube method
  • 40
  • POMD
  • 2
  • 3
  • Speed of sound, m/s ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 2; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Sing-around technique in a fixed-path interferometer
  • 40