Steven Dec - Heats of Solution of Gaseous Hydrocarbons in Water at 25 oC.

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  Publication Details (including relevant citation   information):

  S.F. Dec and S.J. Gill, Journal of Solution Chemistry,   13, 27 (1984)


  The heats of solution at 25°C for a number of hydrocarbon gases   are reported as measured by a calorimetric method. There is   excellent agreement between the standard enthalpy changes of   solution measured calorimetrically and those derived from high   precision temperature dependent solubility measurements. However   the calorimetrically determined standard enthalpies of solution   of a number of gases are greatly improved over values obtained   from low precision temperature dependent solubility measurements.   A method is presented to readily estimate the standard errors in   the standard enthalpy change for any process derived from the   temperature dependence of the equilibrium constant for the   process. Comparison of the standard enthalpies and entropies of   solution of hydrocarbon gases in water shows that the standard   free energies of solution for all hydrocarbon gases investigated   are dominated by unfavorable entropy contributions. A strong   linear correlation between the standard entropy of solution and   the number of hydrogens in the hydrocarbon molecule is found.   This correlation suggests that the hydrocarbon hydrophobic effect   is regulated by the number of allowable configurations of a water   molecule in contact with each C–H group.

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