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 degrees C for 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 measured at 25 degrees C. Partial molar volumes and structural parameters of the molecules investigated were determined. The relations between these data and solubility and polarity were found and discussed. The partial molar volumes for halo derivatives and 6-amino-1,3-dimethyluracil increase, with increasing temperature whereas those for 5-aminouracil, 6-aminouracil, and 5-nitrouracil remain constant within the limit of experimental error.