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How do i determine whether a reaction occurs spontaneously

  1. Mar 25, 2007 #1
    how do you determine this, do you hve to take exothermic or endothermic reactions into acount or what
  2. jcsd
  3. Mar 25, 2007 #2
    well ive anshttp://www.csun.edu/~psk17793/G%20Chemistry/spontaneous_processes.htmwered [Broken] the question myself, and if u need help here's a link
    Last edited by a moderator: May 2, 2017
  4. Mar 25, 2007 #3


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    Spontaneous processes result in the lowering of the total Gibbs Free Energy (G).

    For a chemical reaction to be spontaneous, ΔG must be negative.
    It is possible to have both exothermic (ΔH < 0) as well as endothermic (ΔH > 0) spontaneous reactions.

    ΔG = ΔH – T * ΔS
    Where ΔG is the change in the Gibbs Free Energy, ΔH is the change in enthalpy, ΔS is the change in entropy, and T is the temperature the reaction occurs at (in Kelvin).
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