Original Articles
M. Kondaiah, K. Sreekanth, Sk.
Abstract
Ultrasonic velocities, u, and densities, ρ of 0.5 m, 1.0 m and 1.5 m aqueous ethylene glycol and propylene glycol solutions in iso-propanol have been measured over the entire composition range at 308.15 K. From this experimental data, deviation in ultrasonic velocity, Δu, deviation in isentropic compressibility, Δks, excess intermolecular free length, E f L , excess acoustic impedance, ZE and excess molar volume, E Vm have been determined. It has been observed that ultrasonic velocity increases first and attained a maximum value thereafter decreases. Negative values of E Vm , Δks , E f L and positive values of Δu, ZE, are observed over the entire composition range in the mixtures studied. The observed negative and positive values of various excess and deviation parameters are attributed to the existence of strong interactions such as geometrical fitting of smaller molecules into the voids created by larger molecules in the liquid mixtures. The measured values of ultrasonic velocity for all the investigated solutions have been compared with the theoretically estimated values using empirical relations such as, Nomoto, Van Dael and Vangeels ideal mixing relation and Impedance dependence relation.