US EPA

3829185 

Journal Article 

Effect of temperature and solvents on ultrasonic velocity and thermodynamic parameters of cyclohexane-1,1-diylbis(2-methyl-4,1-phenylene)dibenzoate solutions 

Patel, C; Bhavin, D; Parsania, PH 

2015 

Yes 

Journal of the Indian Chemical Society
ISSN: 0019-4522 

92 

9 

1395-1407 

WOS:000364349000008 

The present work describes physico-chemical parameters of cyclohexane-1,1-diylbis(2-methyl-4,1-phenylene)dibenzoate (MBCBZ). The density (p), viscosity (TI) and ultrasonic speed (U) of pure solvents : 1,4-dioxane (DO), chloroform (CF), ethyl acetate (EA), tetrahydrofuran.(THF) and MBCBZ solutions of different concentrations were investigated at four different temperatures : 298, 303, 308 and 313 K to understand the effect of solvents on molecular interactions. Various acoustical and thermodynamic parameters such as ultrasonic speed (U), adiabatic compressibility (kappa(s)), Rao's molar sound function (R-m), specific acoustical impedance (Z), van der Waals constant (b), internal pressure (pi), viscous relaxation time (tau), free volume (V-f), intermoleoular free path length (L-f) and classical absorption coefficient (alpha/f(2))(cl) have been determined and correlated with concentration (C). A fairly good to excellent correlation between a given parameter and concentration is observed. Studied aeoustical and thermodynamic parameters indicated existence of strong molecular interactions in the solutions. Gibb's free energy of activation (Delta G*) is found to be both concentration and temperature dependent. Both enthalpy of activation (Delta H*) and entropy of activation (Delta S*) are found to be concentration dependent. 

Density; viscosity; ultrasonic speed; molecular interaction