Densities, viscosities, speed of sound and some acoustical parameter studies of substituted pyrazoline compounds at different temperatures

Abstract

Density, viscosity and ultrasonic velocity of pure dioxane and ligands, 3-(2-hydroxy-5-methyl phenyl)-5-phenyl-Δ²pyrazoline [HMPPIZOLINE] and 3-(2-hydroxy-5-methylphenyl)-1,5-di-phenyl-Δ²pyrazoline [HMPPPIZOLINE] in different mole fraction of dioxane-water mixture have been investigated at different temperatures (298.15, 303.15 and 308.15) K. Acoustical parameters such as adiabatic compressibility (β), intermolecular free length (L_f), acoustical impedance (Z), apparent molar compressibility (_β), apparent molar volume (_V), relaxation time (Γ), absorption coefficient, free volume, Gibb’s free energy and relative association (R_A) have also been determined from the experimental data of density, viscosity and ultrasonic velocity. An excellent correlation between a given parameters is observed at all temperatures and the result suggests the presence of molecular interactions. The effect of temperature variations on the strength of molecular interaction has also been studied and the data have been quantitatively explained in terms of solute-solvent interaction.