PARTIAL MOLAL VOLUME AND PARTIAL MOLAL ISENTROPIC COMPRESSIBILITY OF L-ISOLEUCINE IN AQUEOUS K2SO4, KNO3 AND KCL SOLUTIONS AT THE TEMPERATURES (303.15, 308.15, 313.15, 318.15 AND 323.15 K)

Abstract

The apparent molal volume  (f ) apparent molal isentropic compressibility(f)of amino acid; L-isoleucine in aqueous solutions of 0.5Mfv) and ( K2SO4,1M KNO3 and 1.5M KCl have been calculated at several temperatures by using density and isentropic compressibility values. These  0fparameters values have been used to derive the apparent molal volume at infinite dilution i.e. partial molal volume, ( v ) and apparent molal  0fisentropic compressibility at infinite dilution i.e. partial molal compressibility, ( k ) for amino acid in the said aqueous solution of electrolytes. The  0fobserved  v values for the studied amino acid in aqueous electrolyte medium have been found to be larger in magnitude than those of corresponding values in water. The negative values with few positive apparent isentropic compressibility values have been found in all the system under investigation. The negative apparent isentropic compressibility values indicate that the water molecules around the amino acid molecules are less compressible than the water molecules in the bulk solvent. This behavior has been discussed in terms of electrostatic forces operative between zwitter-ions and ions of solutions.