Thermodynamics Research Center / ThermoML | Thermochimica Acta

D2O-H2O solvent isotope effects on the enthalpy of 1,3- dimethylpropyleneurea hydration at temperatures from (278.15 to 313.15) K and atmospheric pressure

Batov, D. V.[Dmitriy V.], Ivanov, E. V.[Evgeniy V.]
Thermochim. Acta 2011, 514, 1-2, 16-21
ABSTRACT
The enthalpies of solution of 1,3-dimethylpropyleneurea in ordinary (H2O) and heavy (D2O) water were measured at (278.15, 283.15, 288.15, 298.15, and 313.15) K and atmospheric pressure. Standard enthalpies and heat capacities of solution (hydration), along with D2O-H2O solvent isotope effects on the quantities studied, were computed. The enthalpies of a solute dissolution as well as corresponding solvent isotope effects were found to be negative by sign and decreasing in magnitude with increasing temperature. It was established that the hydration (mainly of a hydrophobic type) is enhanced in D2O and on going from 1,3-dimethylethyleneurea (1,1,3,3-tetramethylurea) to 1,3-dimethylpropyleneurea, whereas the enthalpy-isotope effects become the less appreciable in the latter case.
Compounds
# Formula Name
1 C6H12N2O 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone
2 H2O water
3 D2O water-d2
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
  • Refractive index (Na D-line) ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Standard Abbe refractometry
  • 1
  • POMD
  • 1
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Pycnometric method
  • 1
  • POMD
  • 1
  • 3
  • Molar enthalpy of solution, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 1; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • ISOPERIBOL
  • 5
  • POMD
  • 1
  • 2
  • Molar enthalpy of solution, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Molality, mol/kg - 1; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • ISOPERIBOL
  • 5