ULTRASONIC INVESTIGATION OF MOLECULAR ASSOCIATION IN BINARY-MIXTURES - DIOXAN PLUS FORMIC-ACID, SALICYLIC-ACID AND BENZOIC-ACID

Complex formation in binary mixtures of carboxylic acids viz. salicyli c acid, benzoic acid and formic acid in dioxan has been studied throug h ultrasonic velocity measurements (at 2 MHz) in the concentration ran ge 0.01-0.10 at 25, 35 and 45 degrees C. The ultrasonic velocity data are used to estimate adiabatic compressibility, intermolecular free le ngth, specific acoustic impedance, molar sound velocity and molar comp ressibility. These in turn are used to study the solute-solvent intera ctions in these systems. The excess volume results evaluated through d ensity measurements are found io support the existence of complex form ation. The ultrasonic velocity data of dioxan + formic acid have been analyzed in terms of Nomoto and ideal mixing relations.