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Densities of binary mixtures of 2-methoxyethanol (2-MeO-EtOH) and 2-ethoxyethanol (2-EtO-EtOH) with hexylamine (HLA), diethylamine (DEA), triethylamine (TEA), tert-butylamine (TBA), aniline (ANL), and benzylamine (BLA) have been determined at varying compositions of the alkoxyalkanols at 298.15 K. The excess molar volumes, VE, of the binary mixtures were calculated from the experimental density data of the mixtures and the component single solvents. The calculated excess molar volumes were fitted into the Redlich-Kister polynomial to obtain the fitting coefficients and standard deviations. The excess molar volumes of the binary mixtures of all the solvent systems investigated were negative over the entire range of the solvents composition. The negative values were attributed to stronger hydrogen bond formations between the unlike molecules of mixtures than those between the like molecules of the pure components. The magnitude of the excess molar volumes of the binary mixtures of 2-methoxyethanol and the aliphatic amines were in the order TBA > TEA > DEA > HEA. For the two aromatic amines, the magnitudes were in the order BLA > ANL. For binary mixtures of the amines and 2-ethoxyethanol, the magnitudes were in the order DEA > TEA > TBA > HEA at compositions where the mole fraction of 2-EtO-EtOH was ≤0.5 and TBA > TEA > DEA > HEA above 0.5 mole fraction of 2-EtO-EtOH.

Kinematic viscosities (ν) of binary mixtures of ethyl acetoacetate (EAA) + aliphatic ketones (C4-C9) have been determined as a function of composition at 298.15 K. The dynamic viscosity (η), excess viscosity and excess Gibbs free energy of activation for viscous flow, (∆G *E) were also calculated. Excess viscosities (η E) and excess Gibbs free energies of activation for viscous flow (∆G *E) were calculated from the experimental viscosity data and were fitted to a Redlich-Kister type polynomial. The excess viscosity shows negative deviations over the entire range of solvents composition for the mixtures of (ethyl acetoacetate) + butan-2-one, hexan-2-one, heptan-2-one, octan-2one and nonan-2-one and a positive deviation for the binary mixtures of ethyl acetoacetate + pentan-2-one system. The (∆G *E) were all positive over the entire range solvents composition for the binary mixtures. The experimental results were used to test some semiempirical equations to correlate viscosity-composition data.

Densities of pure liquids and binary mixtures of diethyl ether (DEE) with 2-alkoxyethanols (2- methoxyethanol, 2-ethoxyethanol and 2-butoxyethanol) have been determined over the entire range of solvent compositions at (293.15, 298.15 and 303.15) K. Excess molar volumes (VM E ) have been calculated from the density data and were fitted into the Redlich-Kister type polynomial equation to obtain the fitting parameters Ai. The values of excess molar volumes, vm E were negative in regions of low diethyl ether (DEE) composition and small positive values were observed in regions of high diethyl ether (DEE) compositions in all the systems studied. VM E values were also found to decrease with increase in temperature and increase in chain length of the 2-alkoxyethanols. The above trends were attributed to the combined effects of disruption and formation of hydrogen bonds between like molecules of 2- alkoxyethanols and unlike molecules of diethyl ether (DEE), respectively.

Investigation on Density (ρ) and viscosity (η) of various binary mixtures of ethylacetoacetate and straight chain aliphatic ketones (butan-2-one, pentan-2- one, hexan-2-one, heptan-2-one, octan-2-one and nonan2-one) have been carried out over the entire solvents composition range at temperatures of 303.15K and 308.15K. From the data obtained, the excess molar volumes (V E ), the excess viscosity (η E ) and excess Gibbs free energy of activation for viscous flow (ΔG*E) have been calculated from the experimental density and viscosity measurements at the working temperatures. Excess molar volumes, V E results are negative and positive over the entire range of mole fractions and become more positive as the chain length increases. The excess viscosities, η E were both positive and negative over the entire mole fraction range. While the observed excess Gibbs free energies of activation of viscous flow, ΔG*E data are positive throughout the entire mole fraction range of solvents composition at all investigated temperatures. These observed results of the excess functions have been interpreted in terms of possible molecular interactions in the binary mixtures.