Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

In this work, densities (poundsl) and refractive indices (n) of N-o-tolyl-2-nitrobenzo- and N-o-tolyl-4-nitrobenzo-, hydroxamic acids have been determined in Dimithylsulfoxide (DMSO) as a function of their concentrations at T = (298.15, 303.15, 308.15, 313.15 and 318.15) K . These measurements were carried out to evaluate some important parameters, viz, molar volumes (V), apparent molar volumes, limiting apparent molar volumes and the slope, molar refractions (RM), polarizability. The related parameters determined are limiting apparent molar expansivity, thermal expansion coefficient and Hepler!|s constant. Excess properties such as excess molar volumes (VE), excess refractive index (nE), excess molar refraction (R E M) have also been evaluated. The excess properties were fitted to the Redlich-Kister equations to estimate their coefficient and standard deviation were determined. The variations of these excess parameters with composition were discussed from the viewpoint of intermolecular interactions in these solutions. The excess properties are found to be either positive or negative depending on the molecular interactions and the nature of solutions. Further, these parameters have been interpreted in term of solute-solute, solute-solvent interaction and structure making ability of solute in DMSO.