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 deg rees C for aqueous solutions of uracil, 5-fluorouracil, 5-chlorouracil, 6-c hlorouracil, 5-bromouracil. 5-iodouracil, 5-aminouracil, 6-aminouracil, 6-a mino-1,3-dimethyluracil, and 5-nitrouracil. The solubility of each compound in water was measured at 25 degrees C. Partial molar volumes and structura l parameters of the molecules investigated were determined. The relations b etween 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-am inouracil, and 5-nitrouracil remain constant within the limit of experiment al error.