Ultrasonic Speed and Related Acoustical Parameters of 1,1ʼ-Binaphthalene-2,2ʼ-diyl Diacetate Solutions at 308.15 K

Abstract

The density (ρ), viscosity (η) and ultrasonic speed (U) (2 MHz) of chloroform, THF, ethyl alcohol, ethyl acetate, 1,4-dioxane and 1,1ʼ-binaphthalene-2,2ʼ-diyl diacetate (DBNA) solutions have been determined at 308.15 K. Various acoustical parameters namely specific acoustical impedance (Z), adiabatic compressibility (κ_a), Van der Waals constant (b), intermolecular path length (L_f), internal pressure (π), Raoʼs molar sound function (R), relaxation time (τ), classical absorption coefficient (α/f²)_cl and solvation number (S_n) have been derived from ρ, η and U data and correlated with concentration (C). A fairly good to excellent correlation has been observed between a particular parameter and C. Linear increase of Z, R, b, (α/f²)_cl and τ (except EA) (R² = 0.90 – 0.999) and linear decrease of κ_s, π and L_f (R² = 0.947 – 0.995) with C supported existence of powerful molecular interactions in the solutions and further supported by nonlinear increase of S_n with C. A fairly constant Gibbs free energy of activation has been observed in all the solvent systems studied.