Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

The solubilities of crystalline compounds, uracil, 5-fluorouracil, 5-chlorouracil, 6-chlorouracil, 5-bromouracil, 5-iodouracil, and 5-(trifluoromethyl)uracil, in water have been determined at 25 deg C by the isothermal saturation method. The molar standard Gibbs energies (AsolGm o ) and the molar entropies of solution (AsolSm o ) were determined on the basis of the solubilities and previously determined molar enthalpies of solution (AsolHm o ). The thermodynamic parameters of sublimation (AsubGm o , AsubSm o ) were calculated from the previously determined molar enthalpies of sublimation AsubHm o . The values obtained were used for calculation of the thermodynamic parameters of solvation (AsolvGm o , AsolvSm o ). The thermodynamic functions of solvation and solution were correlated with the values of the surface-accessible areas, the partial molar volumes V2 o , the molecular volumes V2 M, and the parameters of the compounds investigated.