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Densities ρ, ultrasonic speeds u, and refractive indices n for pure n-hexane, methylacrylate (MA), ethylacrylate (EA), ethylmethacrylate (EMA), butylacrylate (BA), and of their 36 binary mixtures over the entire composition range were measured at 298.15, 303.15, 308.15, and 313.15 K. Using these data, the excess molar volumes,VE, deviations in isentropic compressibilities, Δks, deviations in molar refractions, ΔRm, and deviations in internal pressure, ΔPi, were calculated for the mixtures at given temperatures. Apparent molar volumes,Vϕ,2, and apparent molar compressibilities,Kϕ,2, of acrylic esters in n-hexane were also calculated. Partial molar volumes,, and partial molar isentropic compressibilities,, at infinite dilution were estimated. Moreover, the optical property and partial molar refraction,, of the systems at infinite dilution were examined. The variations of these parameters and of the optical property suggest that the strength of interactions in these mixtures follow the sequence: MA < EA < EMA < BA. [ABSTRACT FROM PUBLISHER]

Abstract: The densities, ρ and refractive indices, n D of binary mixtures of dimethylsulphoxide (DMSO) with poly(ethylene glycol) 200 (PEG200), poly(ethylene glycol) 300 (PEG300) and poly(ethylene glycol) 400 (PEG400) over the entire composition range were measured at temperatures (298.15, 303.15, 308.15, and 313.15K) and at atmospheric pressure. From the experimental data, the excess molar volumes, V m E and excess refractive indices, n D E were calculated. The partial molar volumes, and of the components at infinite dilution and excess partial molar volumes, and of the components at infinite dilution have been calculated. The V m E values were negative and n D E were positive for all the three systems at each investigated temperatures. The results indicate the presence of specific interactions between DMSO and PEG molecules. The negative deviations in V m E values follow the order: PEG200

The present work reports the results of densities, ρ, viscosities, η, ultrasonic speeds, u, and refractive indices, n, of pure styrene (STY), acetone (ACT) and dimethylsulphoxide (DMSO) and of their binary liquid mixtures over the entire composition range at 298.15, 303.15, 308.15, and 313.15 K. The excess molar volumes, VE, excess intermolecular free lengths, [image omitted], deviations in isentropic compressibilities, Δks, viscosities, Δη, and in refractive indices, Δn were calculated from the experimental data. Partial molar volumes, [image omitted], and partial molar compressibilities, [image omitted], of ACT and DMSO in styrene at infinite dilution and at different temperatures have been evaluated. Apart from using density data for the calculation of VE, excess molar volumes have also been estimated by using the Flory's statistical theory and refractive index measurements. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents experimental data for densities, ρ, viscosities, η, ultrasonic speeds, u, and refractive indices, n, of pure styrene (STY), chlorobenzene (CB), ethylalcohol (EA) and of their binary liquid mixtures over the entire composition range at 298.15, 303.15, 308.15, 313.15 K. The uncertainties in density, ultrasonic speed, viscosity, and refractive index measurements are ±0.0001 g cm−3, ±0.15 m s−1, ±0.003 mPa s, and ±0.0002 units, respectively. From these experimental data, excess molar volume, deviations in isentropic compressibility, viscosity and in refractive index and internal pressure are calculated for all the binary mixtures, over the entire composition range. The apparent molar volume, V ϕ ,2, and apparent molar compressibility, K ϕ ,2, of CB and EA in styrene were also calculated. Partial molar volume,V−ϕ ,2 0, and partial molar compressibility, K−ϕ ,2 0, were estimated by using the values of V ϕ ,2 and K ϕ ,2 of CB and EA in styrene at infinite dilution. The excess and deviation functions were fitted to Redlich and Kister type polynomial equation. Moreover, theoretical predictions of refractive index of the two binary mixtures are made on the basis of empirical and semiemperical relations by using the experimental values of the pure components. The results provide information on the molecules in the pure liquids as well as in the binary mixtures. [Copyright &y& Elsevier]

The refractive indices, nD, of pure benzene and 1,2-dichloroethane (DCE) and those of their binary mixtures have been measured over the whole composition range and at 298.15, 303.15, 308.15, 313.15, and 318.15 K. Using the experimental nD data, deviations in refractive indices, ΔnD, molar refraction, ΔRm, reduced free volume, Δ(V/Rm), and internal pressure, ΔPint, have been estimated. Parameters of polynomial equations, which represent the composition dependence of physical and derived properties, are gathered. The results are discussed in terms of molecular interactions between the component molecules. Applicability of eight different refractive index mixing rules - Lorentz-Lorenz, Weiner, Gladstone-Dale, Heller, Arago-Biot, Newton, Eykman, and Oster's relation - is tested against the measured results, and good agreement has been obtained. Moreover, molecular radii, r, and average molecular radii (rmix) of the liquids and their mixtures have been calculated. [ABSTRACT FROM AUTHOR]

Abstract: Density, ρ, viscosity, η, and refractive index, n D measurements have been carried out on α-amino acids, glycine, dl-alanine, l-serine, and dl-valine (0.1 to 0.5) M in 0.2 M aqueous d-glucose solution at T =(298.15, 303.15, 308.15, and 313.15) K. These measurements have been performed to evaluate some important parameters, viz, apparent molar volume, ϕ v, limiting apparent molar volume, transfer volume, , viscosity A and B-coefficients of Jones–Dole equation, variation of B with temperature, dB/dT, free energy of activation per mole of solvent, , and solute, , respectively, and molar refractive index, R D. These parameters have been interpreted in terms of solute–solute and solute–solvent interactions and structure making/breaking ability of solutes in the given solution. In addition to this, , B-coefficient and , have been split into group contributions of the amino acids using their linear correlation with number of carbon atoms in the alkyl chain of the amino acids. [Copyright &y& Elsevier]