Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Physical properties of aqueous solutions of drugs are required to assess the biological activity of that particular drug in treatment of the disease. The most important of the physical parameters are density and speed of sound. From this point of view, we have measured densities and speeds of sound of procaine hydrochloride (Procaine HCl) in aqueous and in 0.06 mol kg 1 and 0.1 mol kg 1 aqueous solutions of sodium chloride and potassium chloride at three different temperatures i.e. T = (288.15, 298.15 and 308.15) K in the concentration range of (0.01 0.1) mol kg 1. Density and speed of sound data were used to evaluate different thermodynamic properties such as apparent molar volume oV/P of solute, isentropic compressibility ojsP of solution, apparent molar isentropic compressibility oj/P of solute i.e. procaine hydrochloride (Procaine HCl) in water and in aqueous solutions of 0.06 and 0.1 mol kg 1 sodium chloride and potassium chloride. The limiting apparent molar expansivity oE0 / P of procaine hydrochloride and coefficient of thermal expansion oa P of procaine hydrochloride have also been estimated. Infinite dilution values of V/ and j/ were also obtained from extrapolation to zero molality and have been utilized in obtaining transfer volumes oDtrV0 / P and transfer compressibilities oDtrj0 / P of procaine hydrochloride from water to aqueous solutions of 0.06 mol kg 1 and 0.1 mol kg 1 sodium chloride and potassium chloride at different temperatures. The results are interpreted in terms of different interactions between solute and solvent molecules (solute-solute and solute-solvent interaction).