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    CH3CH2COOH + CH3CH2OH = CH3CH2COOCH2CH3 + H2O ∆H = –22 kJ mol–1
    If Kc is 4.45 and and you increase the temperature at equilibrium why do the number of moles of products decrease
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    (Original post by honeylooloo)
    CH3CH2COOH + CH3CH2OH = CH3CH2COOCH2CH3 + H2O ∆H = –22 kJ mol–1
    If Kc is 4.45 and and you increase the temperature at equilibrium why do the number of moles decrease?
    Moles of what? Reactants, products, overall?

    Overall - no change
    Products - decrease
    Reactants - increase
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    (Original post by TeachChemistry)
    Moles of what? Reactants, products, overall?

    Overall - no change
    Products - decrease
    Reactants - increase
    Products, could you please explain to me why it decreases?
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    Do you understand Le Chatelier?
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    (Original post by Pigster)
    Do you understand Le Chatelier?
    Yeah but I can't understand what increasing the temperature has to do with moles?
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    (Original post by honeylooloo)
    Yeah but I can't understand what increasing the temperature has to do with moles?
    Look at the sign of the enthalpy change that comes with the reaction. If you increase the temperature which way will the equilibrium shift?
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    (Original post by TeachChemistry)
    Look at the sign of the enthalpy change that comes with the reaction. If you increase the temperature which way will the equilibrium shift?
    Equilibrium will shift to the left
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    (Original post by honeylooloo)
    Equilibrium will shift to the left
    Correct. So how does this affect the moles of products?
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    If a system in equilibrium encounters a change, the equilibrium will shift to counteract the change. So here an increase in temperature will cause the equilibrium to shift to decrease the temperature by moving in the endothermic direction ie the left so the number of moles of reactants increases and numbers of moles of product decreases.

    You know the left is the endothermic direction as the enthalpy change that is given is negative ie the right side of the equation is exothermic so the left muse be endothermic.
 
 
 
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