Journal Articles (before-1995)

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Subject: search.filters.subject.Enthalpies

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    Excess Enthalpies of some Binary Mixtures of 1,2-Dichloroethane and Hydrocarbons
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (1), 1977) Mahl, B. S.; Khurma, J. R.
    The excess enthalpies of mixtures of 1,2-dichloroethane with cyclohexane, benzene, toluene, o-, in- and p-xylenes have been measured at 298.15 K. 7/E values for the first two systems are found to be positive over the entire composition range whereas //E changes sign with composition in the rest of the systems. Examination of the results shows that there appears to be some kind of specific interaction between aromatic hydrocarbons and 1,2-dichloroethane.
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    Microcalorimetric studies: Enthalpies of formation of Cr(PF3)6 and Ni(PF3)4
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (09), 1974) S. Brown, D. Lalage; Connor, Joseph A.; Skinner, Henry A.
    Measurements of the heats of iodination of hexakis(trifluorophosphine)chromium(0) and of tetrakis(trifluorophosphine)nickel(0) were carried out by high temperature microcalorimetry. Standard enthalpies of formation were derived: ΔH°f(Ni(PF3)4, liq)=–961.9 ± 3 kcal mol–1(–4025 ± 12 kJ mol–1), ΔH°f(Cr(PF3)6, c)=–1446.4 ± 4 kcal mol–1(–6052 ± 17 kJ mol–1). The mean bond dissociation energies, D(Ni—PF3) and D(Cr—PF3) were evaluated as 35.2 ± 0.8 and 25.5 ± 1 kcal mol–1 respectively; these values compare very closely with the values D(Ni—CO) and D(Cr—CO) in Ni(CO)4 and Cr(CO)6.
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    Experimental Enthalpies for Nitrous Oxide Vapour in the range 1 to 49 bar and 273.15 to 373.15 K
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Dawe, Richard A.; Snowdon, Peter N.
    The enthalpy-pressure behaviour for nitrous oxide along eleven isotherms in the vapour phase has been determined from measurements of the Joule-Thomson effect. These measurements and the derived enthalpy values are reported in the form of polynomial functions of pressure. Up to 20 bar the precision is estimated to be 4 J mol-1 and at 45 bar between 8 and 15 J mol-1 depending on the temperature. From these values a table of high pressure enthalpies of nitrous oxide vapour is presented for the range 273.15 to 373.15 K.
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    Flame-Photometric Determination of the Standard Enthalpies of Formation of Al(0H)2 and AIO
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (2), 1972) Jensen, D E; Jones, G A
    Spectrophotometric studies have been made of gas-phase aluminium-containing species in fuel-rich premixed laminar atmospheric-pressure H2+ N2+ O2 flames to which this metal is added. The principal compound formed by Al under the conditions of this work is Al(OH)2. Standard zero-point enthalpy changes and equilibrium constants are determined for two important reactions: Al + 2H2O ⇌ Al(OH)2+ 2H; ΔH°0=–95 ± 30 kJ mol–1, K= 3.0 exp (4300/T);, Al + OH ⇌ AlO + H; ΔH°0=–172 ± 20 kJ mol–1, K= 0.67 exp (19200/T). The results lead to standard zero-point enthalpies of formation for Al(OH)2(g) and AlO(g) from Al(g), O2(g) and H2(g) of –1005 ± 30 and –349 ± 20 kJ mol–1 respectively.
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    Excess Enthalpies and Weak Interactions in Liquid Mixtures of Methylene Chloride with Benzene, Toluene and Xylenes
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (8), 1972) Nigam, R K; Mahl, B S
    Excess enthalpies as a function of compositions have been measured by a newly designed calorimeter for the mixtures of methylene chloride with benzene, toluene, o-, m- and p-xylene at 25 and 30°C. The excess enthalpy HE for these mixtures is found to be negative with a positive temperature coefficient. Analysis of the HE data suggests the existence of specific interactions between methylene chloride and the aromatic hydrocarbons studied.