Densities, ultrasonic speeds, refractive indices, and COSMO analysis for binary mixtures of dichloromethane with acetone and dimethylsulfoxide at T = (298.15, 303.15, and 308.15) K

ABSTRACT

Experimental densities (ρ), ultrasonic speeds (u), and refractive indices (n_D) of binary mixtures of dichloromethane (DCM) with acetone (ACT) and dimethylsulfoxide (DMSO) were measured over the whole composition range at T = 298.15, 303.15, and 308.15 K. From the experimental data, excess molar volume (V^E), deviations in isentropic compressibility (Δk_s), deviations in intermolecular free length (ΔL_f), deviations in refractive index (Δn_D), and deviations in ultrasonic speed (Δu) were calculated. Moreover, the Benson–Kiyohara theory was applied to the binary mixtures to obtain the theoretical Δk_s values. The COSMO calculations depending on density functional theory were utilized to estimate the σ-profiles for the DCM, ACT, and DMSO. The interpreted σ-profile trends were found supportive with the experimental findings. Applicability of different empirical and semi-empirical relations of refractive index data were tested against the measured results, and good agreement has been obtained. The possible results of intermolecular molecular interactions among mixture components were interpreted.

KEYWORDS:

• Binary mixtures
• COSMO analysis
• experimental studies
• intermolecular interactions
• mixing rules

Acknowledgment

The authors thank University Malaya for the grants that have funded for our research: UMRG RG293-14AFR and PG191-2016A.