Background:
The Binary mixtures of the isopropanol/isobutanol/isoamylalcohol with equimolar mixture of ethanol and formamide consists
of different ultrasonic properties have been studied at room temperature at a fixed frequency of 2 MHz. The ultrasonic related physical parameters like
velocity (U), density (ρ), adiabatic compressibility (βad), intermolecular free length (Lf) ,acoustic impedance (Z) etc. have been studied. The theoretical evaluation of ultrasonic velocity in liquid mixtures offers a transparent method for the study of the nature of molecular interactions in the mixtures
besides verifying the applicability of different theories such as Nomoto’s, Van Dael and Vangeel’s, Impedance Dependence relation, Junjie’s relation,
Rao’s specific sound velocity relation and Jacobson’s relations, Percentage deviations of theoretical ultrasonic velocities from experimental values in
the mixtures of all liquid mixture and also calculated values of ultrasonic velocity from polynomials of for all the schemes with mole fraction (x) of
isopropanol/isobutanol/isoamyl alcohol.
Objective:
The main focus of the present work was to prepare the structural changes associated with the liquid mixtures having weakly interacting
components as well as strongly interacting components. The study of molecular is association in mixtures having exact information of thermodynamic
mixing properties such as adiabatic compressibility, intermolecular free length, free volume, internal pressure and molar volume and has a great importance in theoretical and applied areas of research. The ultrasonic study has been a subject of active interest during the past many years. This branch
of physical sciences has played a great role in deciding the interactions between the molecules of compounds under study not only that, but also it
exists a potential tool in evaluating energy exchange between various degrees of freedom and nonlinear properties in binary liquid mixtures.
Methods:
The binary liquid mixtures were prepared by mixing the two components, by weight, using an electronic analytical balance (Reptech RA2012) accurate to within ±0.0001 g. The average uncertainty in mole fraction of binary mixtures was estimated to be ±0.0001. To avoid losses of solvent due to evaporation, mixtures were stored in specially designed ground-glass airtight ampoules and placed in a dark place to avoid photolytic effects.
Results:
These empirical fittings of data are described qualitatively and quantitatively using experimental speed data even in the specific interaction
predominant region where non-ideal behavior of the mixture is observed. The values of sound velocities and percentage deviation, (after determining
the co-efficient in the polynomial equations by applying least squares method) have been compiled in the tables respectively.
Conclusion:
The ultrasonic velocities and densities for all the three mixtures are measured and the values of are calculated from these values.The
observed trends of and indicate the presence of weak interactions and the strength of these interactions follow the order
EMM+IPA>EMM+IBA>EMM+IAA. Besides, the ultrasonic velocities gauge from different velocity theories are correlated with the experimentally
measured ultrasonic velocities. Among these theories the Jacobson’s velocity equation gives good result between the experimental and theoretical
ultrasonic velocity values for all the binary mixtures occupied.
Acoustical Studies on Molecular Interactions in Binary Liquid Mixtures at 303 K