Paolo Gianni

Group contributions to the thermodynamic properties of non-ionic organic solutes in dilute aqueous solution

The thermodynamic properties ΔGho,ΔHho, and ΔCp,hoassociated with the transfer of non-ionic organic compounds from gas to dilute aqueous solution and the limiting partial molar properties Cpo,2 and V22 of these compounds in water are described through a simple scheme of group contributions. A distinction is made between groups made only of carbon and hydrogen, and functional groups i.e. groups containing at least one atom different from carbon and hydrogen. Each group is assigned a contribution, for each property, through a least squares procedure which utilizes only molecules containing at most one functional group. Finally, for compounds containing more than one functional group, correction parameters are evaluated as the differences between the experimental values and those calculated by means of the group contributions. The different behavior of hydrophilic compared with hydrophobic groups is discussed for the various properties. A rationale for the correction parameters, i.e. for the effects of the interactions among hydrophilic groups on the thermodynamic properties, is attempted.

Partial Molar Volumes of Ionic and Nonionic Organic Solutes in Water: A Simple Additivity Scheme Based on the Intrinsic Volume Approach

AbstractPartial molar volumes at infinite dilution,

Excess enthalpies and excess heat capacities of the ternary system ethanol + N,N-dimethyl-formamide + cyclohexane at 298.15 K

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Isothermal vapour/liquid equilibria of binary mixtures with dibutyl ether at 298.15 K

, in water at 25°C for organicelectrolytes and nonelectrolytes are described through a simple additivity schemebased on the intrinsic volume approach. The contributions to

Excess Gibbs energies of the ternary system ethanol+N,N-dimethylformamide+cyclohexane at 298.15 K

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Heat capacities of aqueous mixed electrolyte solutions at high temperatures. Application of the Pitzer equations to the mixed system K−Na−Cl−SO4

of hydrocarbongroups were determined from the “experimental” CH2 increment assuming thatall hydrocarbon portions have the same packing efficiency in aqueous solution.Twenty-two charged and 51 uncharged groups, are assigned a