Journal Articles (before-1995)

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    Vapour Pressure of H218O Ice (—50 to 0°C) and H218O Water (0 to 170°C)
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (10), 1977) Jakli, Gyorgy; Staschewski, D.
    The vapour pressure difference between H216O and highly enriched H218O samples was measured directly with a capacitance type differential monometer between –50 and 80°C and with a U-type mercury manometer between 80 and 170°C. Data for the vapour pressure isotope effect in the ice range gave a good fit to the equation ln([graphic omitted])= 3.710/T+ 0.00132 (223 < T < 273), and those in the liquid range to ln ([graphic omitted])= 5.869/T– 0.0108 (293 < T < 443). From the temperature dependence of the vapour pressure ratios the isotope effects on the heat of sublimation and evaporation were calculated. At the melting point Δ(ΔHsub)= 31 J mol–1 while Δ(ΔHevap)= 77 J mol–1 were found. The results are compared with earlier measurements and with data for the HOH/DOD system, where the isotope effect on the heat of fusion is much larger and of opposite sign.
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    Standard Free Energy of Transfer of Ionic Surfactants from Water to Water+Acetone Mixtures from Vapour Pressure Measurements
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (1), 1977) Treiner, Claude; Besnerais, A. Le
    The standard free energy of transfer, ΔG°t of sodium decylsulphate (SDS) and of decyltrimethyl-ammonium bromide (DTMABr) from pure water to mixtures of water and acetone (AC) have been determined by accurate vapour pressure measurements of dilute solutions at 298.15 K. Precise conductance measurements were also made for the two ionic surfactants in water and in water + AC mixtures in the same solute concentration range. ΔG°t was negative, went through a minimum and increased in the AC rich mixtures for both ionic surfactants. These results are qualitatively similar to those for tetrabutylammonium bromide which forms no micelles in the same solvents; they are also consistent with the results inferred from critical micelle concentration (c.m.c.) data on dodecyltrimethylammonium bromide in the same binary solvent system. Using an extrathermodynamic approach for assignment of ΔG°t single ion values, it is shown that these experimental findings can be accounted for solely by the opposing behaviour of anion and cation towards the solvent molecules. Comparison of ΔG°t for SDS and DTMABr (which are almost equal over the whole AC concentration range) indicates that the contribution of the OSO–3 group is of the same sign (positive from water to water + AC mixtures) and virtually equal to that of the bromide ion.
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    Thermodynamic Properties of Aliphatic Halogen Compounds: Part 1.—Vapour Pressure and Critical Properties of 1,1,1-Trichloroethane
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (5), 1973) Ambrose, D.; Sprake, C. H. S.; Townsend, R.
    The vapour pressure of 1,1,1-trichloroethane was measured in the range 15 to 200 kPa by comparative ebulliometry, and the critical temperature and pressure were also measured. The observed values of the vapour pressure were fitted by equations, and one of them, a fourth order Chebyshev polynomial, is recommended for use if interpolation between 200 kPa and the critical pressure is required.