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Isothermal vapor-liquid equilibria of mixtures containing organic compounds. Part 5: Excess Gibbs energies of dichloromethane or chlorobutane + linear ether or acetal mixtures at 25°C
No full textVapor-liquid equilibria for dichloromethane or chlorobutane+a linear mono-, or diether (diethyl ether, dipropyl ether, methyl butyl ether, 1,2-dimethoxyethane,) or an acetal (diethoxymethane), were determined at 25°C by head-space gas chromatographic analysis of the vapor phase directly withdrawn from an equilibration apparatus. Excess Gibbs energies, GE, activity coefficients at infinite dilution, fi o as well as free energy of solvation, ΔGo, were evaluated for all the systems. A tentative approach is presented based either on an additivity scheme of surface interactions and scaled particle theory to calculate group contribution to the free energy of solvation
Isothermal vapour-liquid equilibria of mixtures of organic compounds. Part 8. Excess Gibbs energies of tetrachloromethane + cyclic oxaalkane mixtures at 298.15 K
No full textVapour-liquid equilibria for tetrachloromethane + a cyclic mono or polyoxaalkane (oxetane, oxane, oxepane, 1,3-dioxolane, 1,3-dioxane, 1,3-dioxepane, 1,3,5-trioxane), were determined at 298.15 K by head-space gas chromatographie analysis of the vapour phase directly withdrawn from an equilibration apparatus. Excess Gibbs energies, activity coefficients at infinite dilution, and Gibbs energies of solvation were calculated and briefly discussed for all the systems
Isothermal vapor-liquid equilibria of tetrachloromethane + linear ether or acetal mixtures at 298.15 K
No full textVapor-liquid equilibria for tetrachloromethane + a linear mono-, di-, or triether (diethyl ether, dipropyl ether, dibutyl ether, methyl butyl ether, ethyl butyl ether, 1,2-dimethoxyethane, 1,2-diethoxyethane, di(ethylene glycol) dimethyl ether) or an acetal (dimethoxymethane, diethoxymethane) were determined at 298.15 K by head-space gas chromatographic analysis of the vapor phase directly withdrawn from an equilibration apparatus. Excess molar Gibbs energies GE for the investigated mixtures were determined by a least-squares treatment of the equilibrium data. The GE values are generally negative and, though small, reflect effects due to (i) chain lengthening, (ii) position of the oxygen atom in the chain structure of monoethers, and (iii) distance of two -O-groups in diethers or acetals
Excess enthalpies and excess heat capacities of the ternary system Ethanol + Tetrahydrofuran + Cyclohexane at 298.15 K
No full textIsothermal vapor-liquid equilibria of mixtures containing organic compounds. 7. Excess Gibbs energies of chloroalkane + oxaalkane mixtures at 298.15 K
No full textVapor-liquid equilibria for dichloromethane or chlorobutane+a linear mono-, or diether (diethyl ether, dipropyl ether, methyl butyl ether, 1,2-dimethoxyethane,) or an acetal (diethoxymethane), were determined at 25°C by head-space gas chromatographic analysis of the vapor phase directly withdrawn from an equilibration apparatus. Excess Gibbs energies, GE, activity coefficients at infinite dilution, fi o as well as free energy of solvation, ΔGo, were evaluated for all the systems. A tentative approach is presented based either on an additivity scheme of surface interactions and scaled particle theory to calculate group contribution to the free energy of solvation
Compressibility changes in protonation of some organic aliphatic nitrogen compounds in aqueous solution
No full textDensity and sound velocity of aq. solns. contg. monofunctional primary, secondary and tertiary amines, as well as bifunctional primary and secondary amines (B), and their corresponding hydrochlorides, (BHCl), were measured; the apparent molar compressibilities were calculated. From the limiting apparent molar compressibilities of B, BHCl and HCl in aq. soln. the changes in compressibilities, Δφ°K,S, for protonation of B was obtained. The pattern shown by the Δφ°K,S values was similar to that presented by the changes, ΔX°r, of other thermodn. properties, such as Cp and V, for the formation of BHCl species from B and HCl. The different values of Δφ°K,S obsd. for amines having the same no. of hydrogens bonded to N but differing in the presence of a second hydrophilic group was attributed to the removal of the hydrophobic hydration of the alkyl groups brought about by this center
APPARENT MOLAL HEAT-CAPACITIES OF ORGANIC-COMPOUNDS IN AQUEOUS SOLUTION .3. OMEGA-AMINO ACIDS AND RELATED COMPOUNDS
No full textExcess Gibbs Energies of the ternary system ethanol + N,N-dimethylformamide + cyclohexane at 298.15 K
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