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Excess molar enthalpies, H^E, for the binary mixtures of dimethyl carbonate with o-xylene, m-xylene, p-xylene, ethylbenzene, or ethyl benzoate have been measured by using a flow-type isothermal microcalorimeter at 298.15 K under atmospheric pressure. The experimental H^E values are all positive (endothermic) for these binary mixtures over the entire composition range. The maximum H^E values are in the range 386.6 J·mol^-1 to 674.0 J·mol^-1 and are exhibited at about xi = 0.5, except for the systems containing ethylbenzene and ethyl benzoate. The experimental results were represented accurately by the Redlich−Kister polynomial equation. These new H^E data were also correlated with the Peng−Robinson and the cubic chain-of-rotators (CCOR) equations of state. With two adjustable interaction parameters, the CCOR equation represents the excess enthalpies of these five binary systems satisfactorily.

Excess molar enthalpies, H^E, of binary mixtures of 1-octanol with ethylbenzene, ethyl benzoate, acetophenone, anisole, or methanol have been measured at 298.15 K under atmospheric pressure using an isothermal microcalorimeter. The experimental H^E values are positive for all the binary mixtures over the entire range of compositions. The experimental data have been correlated with the modified Redlich−Kister polynomial equation. The results were qualitatively interpreted in terms of thermodynamic molecular interactions between the mixing components.

Excess molar volumes (V^E) and speeds of sound (u) of the binary liquid mixtures of N,N-dimethylacetamide (DMA) with chloroethanes and chloroethenes at 303.15 K have been measured over the entire range of compositions. The chloroethanes are 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane, and the chloroethenes are trichloroethene and tetrachloroethene. The V^E values are positive in mixtures of N,N-dimethylacetamide with 1,2-dichloroethane and tetrachloroethene. The V^E values are negative over the whole mole fraction range for N,N-dimethylacetamide with 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, and trichloroethene. The speed of sound data were used to compute isentropic compressibilities (κs) and excess isentropic compressibilities (%@mt;sys@%κ%@sx@%s%@be@%E%@sxx@%%@mx@% ). The %@mt;sys@%κ%@sx@%s%@be@%E%@sxx@%%@mx@% values are positive for the system N,N-dimethylacetamide with 1,2-dichloroethane. For the remaining systems, the %@mt;sys@%κ%@sx@%s%@be@%E%@sxx@%%@mx@% values are negative over the entire range of compositions.

Excess molar volumes (V^E) and speed of sound (u) of the binary liquid mixtures of ethyl acetate and butyl acetate with 2-alkoxyethanols at 308.15 K have been measured over the entire range of composition. The 2-alkoxyethanols are 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol. The V^E values are positive in mixtures of ethyl acetate and butyl acetate with 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol. The speed of sound data were used to compute isentropic compressibilities (κs) and excess isentropic compressibilities (κs^E). The κs^E values are negative over the entire range of composition for all the systems of 308.15 K.

Solid−liquid equilibria of 11 binary mixtures of n-alkanes (octadecane, nonadecane, eicosane, heneicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane, and octacosane) in N,N-dimethylformamide (DMF) have been measured from 275 K to the melting temperatures of the n-alkane. The solubility results have been correlated by the Redlich−Kister (two and three parameters) equation and the NRTL equation.

Excess volume (V^E) and viscosity (η) data at 308.15 K were measured for binary systems formed by o-, m-, and p-xylenes with o-nitrotoluene or m-nitrotoluene. Excess volumes were measured directly using a dilatometer. Viscosities were measured with an Ostwald viscometer. The excess volumes and viscosities are discussed in terms of molecular interactions between like and unlike molecules.

The solid−liquid equilibria of 13 binary mixtures of 1,4,7,10,13,16-hexaoxaoctadecane (18-crown-6) in alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butyl alcohol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, and 1-dodecanol) have been determined experimentally by a dynamic method in temperature range from 275 K to the melting temperature of 18-crown-6. The results of solubility have been correlated by the Wilson, NRTL 1, and UNIQUAC equations. The existence of solid−solid first-order phase transition in 18-crown-6 has been taken into consideration in the solubility calculations. The best correlations of the solubility data have been obtained by the Wilson equation, where the average root-mean-square deviation of the solubility temperature is 0.45 K.

The excess molar enthalpies (H^E) at 298.15 K of N,N-dimethylformamide (DMF) with 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, ethyl acetate, and butyl acetate have been measured, using a Parr 1451 solution calorimeter, over the whole mole fraction range. The values of H^E are negative for the mixtures of N,N-dimethylformamide with 1,2-dichloroethane and 1,1,2,2-tetrachloroethane, and an inversion of sign from positive to negative is observed in the mixture N,N-dimethylformamide with 1,1,1-trichloroethane. The H^E values are positive over the whole mole fraction range for N,N-dimethylformamide with ethyl acetate and butyl acetate. The H^E data are interpreted on the basis of possible intermolecular interactions between unlike molecules.

Viscosities have been measured for binary liquid mixtures of trichloroethylene or tetrachloroethylene with 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol at 303.15 K and 313.15 K, over the entire composition range. Viscosities were measured with an Ostwald viscometer.

Volume changes on mixing of ternary liquid mixtures of N,N-dimethylformamide and cyclohexanone with 1-alkanols have been measured as a function of composition at 303.15 K. The alkanols include 1-propanol, 1-butanol, 1-pentanol, and 1-hexanol. The ternary excess volumes were measured directly using a dilatometer. The measured data were compared with predicted values based upon an empirical relation.

Viscosities of binary liquid mixtures of N,N-dimethylformamide with toluene, ethylbenzene, chlorobenzene, bromobenzene, nitrobenzene, and aniline at 303.15 and 313.15 K have been measured over the entire composition range.

Excess volumes and viscosities of binary liquid mixtures of tetrachloroethylene with homologous series of branched alcohols were measured at 303.15 K. The branched alcohols include 2-propanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-butanol, and 2-methyl-2-propanol. Excess volumes (V^E) were measured directly using a dilatometer. Viscosities (η) were measured with an Ostwald viscometer.

Excess volumes, V^E, of binary liquid mixtures of N,N-dimethylformamide with methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone, and cyclohexanone at 303.15 K have been measured with a dilatometer. Excess volumes are negative for the systems of N,N-dimethylformamide with methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, and methyl isopropyl ketone and are positive for N,N-dimethylformamide with cyclohexanone at 303.15 K.

The speed of sound for the binary mixtures of trichloroethylene with branched alcohols has been determined at 303.15 K. The branched alcohols include 2-propanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-butanol, and 2-methyl-2-propanol. Further, isentropic compressibilities (Ks) and deviation in isentropic compressibilities (ΔKs) have been computed from the sound velocity and density data derived from excess volumes. The results show that ΔKs values are positive over the entire range of composition for the systems trichloroethylene + 3-methyl-1-butanol, + 2-butanol, and + 2-methyl-2-propanol, and an inversion of sign from negative to positive is observed for the remaining systems trichloroethylene + 2-propanol and + 2 methyl-1-propanol.