Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Drug interactions in presence of co-solute in aqueous solution have always created an interest in the mind of chemists. The physical properties give an idea of types of interactions taking place in aqueous solution. Volumetric and compressibility are the important physical properties. Keeping this in mind we have measured the densities oqP and speeds of sound ouP of sodium salicylate (NaSl) drug (0.01 0.1) mol kg 1 in 0.06 mol kg 1 aqueous sodium chloride solution and 0.06 mol kg 1 myo-inositol as a function of temperature at T = (288.15, 298.15 and 308.15) K and atmospheric pressure. These values have been used to estimate the apparent molar volume of solute oV/P, apparent molar isentropic compressibility ojsP of solution and apparent molar isentropic compressibility oj/P of solute. The limiting apparent molar expansivity oE0 /P of solute and coefficient of thermal expansion oa P of sodium salicylate in aqueous binary and ternary solutions have also been obtained. Limiting values of apparent molar volume of solute oV0 /P and apparent molar compressibility of solute oj0 /P were obtained from the plots V/ and j/ as a function of molality and have been utilized in obtaining transfer volumes oDtrV0 /P and transfer compressibilities oDtrj0 /P of sodium salicylate from water to 0.06 mol kg 1 aqueous solutions of sodium chloride and myo-inositol at different temperatures. The co-sphere overlap model is used to interpret the values of oDtrV0 /Pand oDtrj0 /P. The Helper s constant has been obtained. It indicates structure making ability of sodium salicylate in aqueous as well as in 0.06 mol kg 1 aqueous sodium chloride and 0.06 mol kg 1 aqueous myo-inositol solutions. The results obtained have been interpreted in terms of various interactions taking place among solute and solvent molecules.