C Gutiérrez Losa

Vapour pressures of (butan-1-ol + hexane) at temperatures between 283.10 K and 323.12 K

Vapour pressures by a static method of n -hexane, n -butan-1-ol, and ( n -butan-1-ol + n -hexane) at temperatures between 283.10 K and 323.12 K at about 5 K intervals, were measured. Activity coefficients and excess molar Gibbs free energies G E m were calculated by Barkers method. Three different types of equations for G E m were used for fitting the experimental results. For alcohol-dilute mixtures, formation of an azeotropic mixture with a minimum boiling temperature was observed.

Excess enthalpies and excess volumes of n-hexane + and of tetrachloromethane + furan, + 1,4-dioxane, + tetrahydrofuran, and + tetrahydropyran

Abstract The excess enthalpies H E and excess volumes V E of n -hexane + furan, + 1,4-dioxane, + tetrahydrofuran, and + tetrahydropyran at 303.15 K have been measured. Mixing is endothermic and excess volumes are found to be positive. H E and V E of tetrachloromethane + furan, + 1,4-dioxane, + tetrahydrofuran, and + tetrahydropyran have also been measured at 283.15 and 303.15 K.

HmE and VmE of some (butanone or dipropylether + an alkanol) mixtures

Abstract Molar excess enthalpies and volumes of (butanone or dipropylether + alkanol) at 298.15 K (in some cases at 308.15 K, too) were measured. The different behaviour observed in each non-alkanol component is put down for the most part to an unlike dipolar contribution. Mixtures containing 2-methylpropan-2-ol deviate from the systematic behaviour of those with n -alkan-1-ols.

HmE, VmE, and GmE of {xCl2HCCHCl2 + (1 − x)C6H14} at several temperatures

Excess molar enthalpies, excess molar volumes, and vapour pressures of (1,1,2,2-tetrachloroethane + n-hexane) between 288.15 and 318.15 K (298.15 to 308.15 K for the vapour pressures) were determined. Activity coefficients and excess molar Gibbs free energies were calculated by Barkers method. Both the strong endothermic character and the positive excess entropy of the mixture suggest an orientational order in 1,1,2,2-tetrachloroethane that is destroyed in the mixing process.

Excess enthalpies of some (chloroalkane + n-alkane) mixtures

Abstract Excess enthalpies at 298.15 K of some (chloroalkane + n-alkane) mixtures are reported. Excess enthalpies at x = 0.5 for 1-chlorobutane + and t-butylchloride + an n-alkane are compared with those of n-hexane+ and 2,2-dimethylbutane + the same n-alkane. In both sets the differences between the excess enthalpies observed for the branched compound and for the normal one are similar.

HmE and VmE of some (1-chlorobutane + alkanol or cyclohexanol) mixtures

Abstract Excess molar enthalpies and excess molar volumes of (1-chlorobutane + an alkanol or cyclohexanol) at 298.15 K (also 308.15 K in some case), were measured. The results were “explained” in terms of interactions involving the chlorine atom. Volumetric behaviour of mixtures containing 2-methylpropan-2-ol is analysed by taking into account the high proportion of cyclic structures in this alcohol and the conversion of linear into cyclic multimers when the mixture is formed.

Excess enthalpies of some binary mixtures. Contribution to the study of the BrO specific interaction

Excess enthalpies of n-hexane + 1-bromohexane, + methylbutylketone, + 1,2-dimethoxyethane, and + acetylacetone; cyclohexane + bromocyclohexane, + di-n-propylether, + methylbutylketone, + 1,2-dimethoxyethane, and + acetylacetone; and 1-bromohexane or bromocyclohexane+din-propylether, + methylbutylketone, + 1,2-dimethoxyethane, and + acetylacetone, at 303.15 K, have been measured as a function of composition. The results for HE of n-hexane+ether or + ketone show the different influence on the excess enthalpy of a repeated functional group in the molecule. In the mixtures containing 1-bromohexane or bromocyclohexane a specific interaction BrO, of acceptor-donor type, exists. Similar conclusions can be obtained from the cyclohexane mixtures; HE is higher, except for 1,2-dimethoxyethane+cyclohexane, than the corresponding n-hexane mixtures, and this can be attributed to dispersive aliphatic-cycloaliphatic interactions.

Excess enthalpies of mixtures containing tetrahydrofurfurylalcohol or tetrahydrofurfurylamine

Abstract Molar excess enthalpies over the whole composition range for tetrahydrofurfurylalcohol or tetrahydrofurfurylamine + cyclohexane, + carbon tetrachloride, + benzene, and + tetrahydrofuran, and of tetrahydrofuran + cyclohexane and + benzene were measured at 303.15 K. A few measurements on tetrahydrofurfurylalcohol + and tetrahydrofurfurylamine + cyclohexane were made at 323.13 K. Partial molar excess enthalpies at infinite dilution of alcohol and amine have been calculated. The results are discussed in terms of hydrogen bonding in tetrahydrofurfurylalcohol and tetrahydrofurfurylamine and of specific interactions between the unlike molecules.

HmE of (an n-alkane + a butanol isomer)

Abstract Excess molar enthalpies of (an n -alkane + a butanol isomer) were measured at 298.15 and 318.15 K. The peculiar shapes of the curves, especially for mixtures containing 2-methylpropan-2-ol, might be put down to the formation of cyclic multimers. The temperature coefficients of H m E are always positive and they increase as the chain-length of the n -alkane increases.

Thermodynamic properties of organic oxygen compounds excess enthalpies for some ester + hexane or + 1-bromohexane, and bromoester + hexane mixtures

Abstract Excess enthalpies of hexane + methyl acetate, +ethyl acetate, +isopropyl acetate, + tert -butyl acetate, +methyl propionate, +ethyl propionate, + tert -butyl propionate, +methyl butyrate, +ethyl-3-bromopropionate, +ethyl-2-bromobutyrate, or +ethyl-4-bromobutyrate, and 1-bromohexane +ethyl acetate, +ethyl propionate, or +methyl butyrate, have been measured at 303.15 K as a function of composition. The results obtained show an increase of H E when the length of either the alcoholic or the acid radical of the ester decreases. In the investigated (aliphatic ester + 1-bromohexane) mixtures the contribution of the specific BrO(carboxylate) interaction to H E seems to be of roughly the same size as the BrO(carbonyl group) one, and in the (bromoester + hexane) mixtures the intramolecular BrO interaction increases as the separation between the bromine atom and the carboxylate group decreases.