Partial Molar Volumes of Aqueous Solutions of Some Halo and Amino Derivatives of Uracil

Apparent molar volumes were experimentally determined at 25, 35, and 45°Cfor aqueous solutions of uracil, 5-fluorouracil, 5-chlorouracil, 6-chlorouracil,5-bromouracil, 5-iodouracil, 5-aminouracil, 6-aminouracil,6-amino-1,3-dimethyluracil, and 5-nitrouracil. The solubility of each compound in water was measuredat 25°C. Partial molar volumes and structural parameters of the moleculesinvestigated were determined. The relations between these data and solubility andpolarity were found and discussed. The partial molar volumes for halo derivativesand 6-amino-1,3-dimethyluracil increase, with increasing temperature whereasthose for 5-aminouracil, 6-aminouracil, and 5-nitrouracil remain constant withinthe limit of experimental error.