Journal of Pure and Applied Ultrasonics

Rita Mehra ¹

Affiliations
1 Acoustic and Environmental Laboratory, Department of Pure and Applied Chemistry, Maharshi Dayanand Saraswati University, Ajmer-305009, IN

Abstract

Ultrasonics has been a powerful tool for studying structural and physico-chemical properties of liquids, liquid mixtures and electrolytic solutions. Ultrasonic speed measurements are helpful for interpreting solute-solute, solute-solvent interactions in aqueous and co-aqueous medium in terms of derived parameters viz. Apparent molal Compressibility, Acoustic Impedance, Intermolecular Free Length etc. Bio-molecules play a vital role in the various biochemical processes occuring in living organisms. Their interactions studies throw a light on the structural complexity of these bio-molecules, which cannot be assessed directly. The present study provides new information from chemical and biological point of view to understand the interactions of threonine and dl-alanine in aqueous or co-aqueous DMF and uracil in the presence of Na₂SO₄ in aqueous urea solution.

Keywords

Density, Internal Pressure, Apparent Molal Volume, Hydration Number, Ultrasonic Velocity.

Full Text

   

Rita Mehra ¹, Meenakshi Pancholi ¹

Affiliations
1 Department of Pure and Applied Chemistry, M.D.S. University, Ajmer-305009, IN

Abstract

The behaviour of mixture of nonane and 1-propanol as a function of temperature and composition has been investigated by measuring sound velocity in conjunction with density at 298, 308 and 318 K. Derived parameters computed from density (ρ) and sound velocity (U) have been used to determine excess molar volumes (V^E), excess isentropic compressibilities (K_S^E) and excess inter molecular free length (L_f). The excess functions have been discussed in terms of intermolecular interactions between the components of binary mixture. The computed results have been fitted to the Redlich-Kister polynomial relation to estimate the smoothening coefficients and standard deviations for this system at the temperatures taken for study.

Full Text

   

Rita Mehra ¹, Ashish Gupta ¹

Affiliations
1 Department of Pure and Applied Chemistry, M.D.S. University, Ajmer-305009, IN

Abstract

Densities(ρ), Viscosities(η) and ultrasonic velocities(u) of binary mixtures of Benzonitrile with 1-propanol were determined using bicapillary pyknometer, Ostwald's Viscometer and ultrasonic interferometer respectively in temperature range of 298.15 to 318.15 K at intervals of 10K. The excess molar volume (V^E), excess viscosities (η^E), excess Gibbs free energy of activation of viscous flow (G^*E), excess isentropic compressibility (K_S^E), excess internal pressure (π_i^E) and excess enthalpy (H^E) have been calculated from the experimental values of ρ, η and u. The results are discussed to explain the strength of interactions between component molecules in the binary mixture taken for study. The data was correlated by using Redlich-Kister polynomial equation stating their dependence on temperature and composition of the mixtures. These properties are used to illustrate the nature of interaction between component molecules.

Full Text