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1.14.55: Process

  • Page ID
    390571
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    In order to document the thermodynamics of processes a convention has been agreed. In general, the thermodynamic variable takes the following form.

    \[\Delta_{\text {proc }} \mathrm{X}^{0}\]

    Here

    1. \(\Delta\) signals a change is the thermodynamic extensive variable \(\mathrm{X}\);
    2. the subscript ‘proc’ signals the process; e.g.
      • \(\mathrm{f} =\) formation
      • \(\mathrm{c} =\) combustion
      • \(\mathrm{vap} =\) vaporisation
      • \(\mathrm{r} =\) chemical reaction
      • \(\mathrm{aln} =\) = solution

    In recognition of the long tradition of using a ‘double-dagger’, a superscript \(\neq\) indicates activation as in the formation of ‘transition state from reactants.

    1. the superscript ‘0’ means under standard conditions which should be defined. Example.
      • \(\Delta_{\mathrm{c}} \mathrm{H}^{0}=\) standard enthalpy of combustion
      • \(\Delta^{\neq} \mathrm{V}^{0}=\) standard volume of activation

    This page titled 1.14.55: Process is shared under a Public Domain license and was authored, remixed, and/or curated by Michael J Blandamer & Joao Carlos R Reis.

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