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Why is this reaction endothermic

  1. May 14, 2016 #1
    1. The problem statement, all variables and given/known data
    At 1500 ° C , CO is formed more than at 1000 ° C. Is the reaction from left to right exothermic or endothermic?
    2. Relevant equations

    C(s) + H2O ↔CO(g) + H2



    3. The attempt at a solution
    I think its Exothermic reaction . The temperature is increased from 1000°C to 1500 °C . If heat increases the CO + H2 (products) shall produced more. Heat is a product in a exothermic reaction .So
    C(s) + H2 ↔CO(g) + H2 +x KJ
    But correct answer seems to be endothermic. I don't know why?
     
  2. jcsd
  3. May 14, 2016 #2

    Ygggdrasil

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    If the system is initially at equilibrium then you add more water vapor, in which direction do you expect the reaction to go? Similarly, if the system is initially at equilibrium then you add more hydrogen gas, in which direction do you expect the reaction to go?
     
  4. May 14, 2016 #3
    If you add hydrogen , the reaction shifts to the right
     
  5. May 14, 2016 #4

    Ygggdrasil

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  6. Jun 3, 2016 #5
    If the products increase when the temperature is increased, then the reaction has to be endothermic. The energy could then be looked at as a reactant and when you increase the reactants, the system has to shift to making more product to compensate- therefore the system would create more CO at higher temperatures.
     
  7. Jun 6, 2016 #6
    In an equilibrium reaction the system always tries to counter the change introduced. In this reaction the temperature increases so the system tries to decrease the temperature by increasing the production of CO. So the forward reaction decreases the surrounding temperature meaning it is an endothermic reaction.
     
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