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Author: search.filters.author.Calado, Jorge C. G.Subject: search.filters.subject.Thermodynamics

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    Thermodynamics of Liquid Mixtures of Methane and Ethene
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (09), 1977) Calado, Jorge C. G.; Soares, VirgIlio A. M.
    The total vapour pressure of liquid mixtures of methane and ethene has been measured as a function of composition at 103.94 and 115.77 K. The results have been used to estimate the excess Gibbs energy GE at these temperatures. The volume of mixing PE has been determined at 103.94 K and is found to be small and negative. In a comparison with the values of GE obtained by other authors, an attempt was made to estimate the value of HE, the molar enthalpy of mixing. The results are interpreted in the light of some simple theories of mixtures, suggesting that this is a case where the Lorentz rule of combination of collision diameters is valid.
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    Thermodynamics of Binary Liquid Mixtures Involving Hydrogen Bromide, Hydrogen Chloride and Xenon
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74 (04), 1978) Calado, Jorge C. G.; Gray, Christopher G.; Gubbins, Keith E.; Palavra, Antonio M. F.; Soares, Virgilio A. M.; Staveley, Lionel A. K.; Twu, Chorng-Horng
    The total vapour pressure of the systems hydrogen bromide+xenon and hydrogen bromide + hydrogcn chloride have been measured as a function of composition at 195.42 K. The results have been used to estimate the excess Gibbs function GE. The volume of mixing J/E has been determined for each system at 195.42 K. The HBr + Xe system departs considerably from ideal behaviour, while HBr+HCl is only slightly nonideal. Neither system exhibits an azeotrope at the temperature studied. These results, together with similar data reported previously for the HCl + Xe system (J.C.S. Faraday I, 1975, 71, 1372), are compared with theoretical calculations based on perturbation theory for liquids of nonspherical molecules. Agreement is good for all three systems. The results show that both dipolar and quadrupolar forces for the 1-IC1 and HBr molecules have a large eifect on the phase diagram, while other types of anisotropic intermolecular forces (overlap, dispersion, induction) appear to have a considerably smaller effect.
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    Thermodynamics of the Liquid System Methane+Propane
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (08), 1974) Calado, Jorge C. G.; Garcia, Gerald A.; Staveley, Lionel A. K.
    The total vapour pressure of liquid mixtures of methane and propane has been measured as a function of composition at temperatures of 115.77 and 134.83 K. The activity coefficient of methane f\ and the excess Gibbs function of mixing GB have been evaluated from the vapour pressure measure ments, and the heat of mixing and the excess entropy of mixing SE have been estimated from the temperature dependence of GE and compared with direct calorimetric values. Values of the excess thermodynamic functions have been calculated from a simplified version of the Flory theory of mixtures, with allowance for departures from the geometric mean (Berthelot) combining rule. Calculations show that these deviations are very small, but not negligible.