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Why does decrease of temperature increase spontanity of a reaction?

  1. Apr 23, 2010 #1
    Hello everyone,

    I always though when reactants are heated up, there are more collisions and more like a reaction is to take place. However this is not the case for spontaneous reaction according to Gibbs equation. Why is that? Thanks :smile:
     
  2. jcsd
  3. Apr 23, 2010 #2

    Mapes

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    I'm not sure how you've reached this conclusion. At constant temperature and pressure, reactions with a negative value of [itex]\Delta G=\Delta H-T\Delta S[/itex] are spontaneous. Since the entropy of a reaction can be positive or negative, we can't say anything absolute about the influence of temperature on spontaneity.
     
  4. Apr 24, 2010 #3
    Not true, it all depends on the relative magnitudes (and signs) of the enthalpy and entropy terms. Here's a video I found a while back; it does a pretty good job of explaining the equation in intuitive terms.

     
    Last edited by a moderator: Sep 25, 2014
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