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Homework Help: Chemical equilibrium

  1. Apr 20, 2010 #1
    Hey all the people reading this, Just wondering if anyone can explain how a equilibrium system changes with a increase/decrease in temperature occurs.


    I've been taught that: If my reaction is exothermic i.e. reactants -> products + energy; and i am going to decrease temperature it would be said that the energy acts as a 'product' therefore to counteract this the system would have to convert the loss of energy to enthalpy or something.

    could someone please help me with this!!

    Thank you! - sirsh.
     
  2. jcsd
  3. Apr 20, 2010 #2

    Borek

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    Staff: Mentor

    What you refer to is LeChatelier's principle. Exotermic reaction equilibrium shifts to the left when temperature increases, endotermic reaction equilibrium shifts to the right when temperature increases.

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    methods
     
  4. Apr 20, 2010 #3
    So. temperature is increased: Reactants -> products + energy then we will see a shift to the left. if the temp for this exothermic reaction is decreased the reaction will shift to the right? and then the same for endothermic in the reaction where temperature is increased: reactants + energy -> products, when the temp increases equilibrium shifts to the right and when decreases it shifts to the left. can you please explain to me why? if thats not too much to ask. thanks alot!
     
  5. Apr 20, 2010 #4

    Borek

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    Staff: Mentor

    http://en.wikipedia.org/wiki/Le_chatelier's_principle

    In the exothermic reaction - when temperature goes up - shifting equilibrium to the left lowers temperature of the reaction mixture. That a direct application of principle. Similar thinking for endothermic reaction and increased temp.

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