In an endothermic reaction, increasing temperature will increase the forward rate constant, which increases the K constant.
For an exothermic reaction, would it be the opposite? Can someone explain this concept with exothermic reactions?
Effect of Temp. on K constant
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Re: Effect of Temp. on K constant
from my notes:
-for exothermic rxn: when temp increases, shifts to reactants (left) to decrease K
-for endothermic rxn: when temp increases, shifts to products (right) to increase K
Also, you can think of temperature as a reactant or product (delta H). If it's exothermic you have heat as a product added to the right side (products). By Le Chatlier's Principle, if you add more heat to the right side (increase temp) it'll cause a shift to the left (reactants) to relieve that change. Same goes for endothermic, just the opposite.
-for exothermic rxn: when temp increases, shifts to reactants (left) to decrease K
-for endothermic rxn: when temp increases, shifts to products (right) to increase K
Also, you can think of temperature as a reactant or product (delta H). If it's exothermic you have heat as a product added to the right side (products). By Le Chatlier's Principle, if you add more heat to the right side (increase temp) it'll cause a shift to the left (reactants) to relieve that change. Same goes for endothermic, just the opposite.
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Re: Effect of Temp. on K constant
If you consider how K is represented by the ratio of products to reactants, then yes, as previously stated since increasing temperature in an exothermic reaction will lead to more products being formed, the value of k will decrease accordingly.
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Re: Effect of Temp. on K constant
It boils down to that in an endothermic reaction, an increase in temp increases the rate constant of the forward reaction. In an exothermic reaction, the increase in temp increases the rate constant of the reverse reaction. Hope this helps!
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Re: Effect of Temp. on K constant
Yes, when you increase temperature when the reaction is exothermic, it favors the reactants. This is because in an endothermic reaction, heat is a product (released). So in order to comp for this, temperature will increase the reactants.
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Re: Effect of Temp. on K constant
For an exothermic reaction, if temperature increased, the K would decrease
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Re: Effect of Temp. on K constant
Yes, it would be the opposite for an exothermic reaction, as when the temperature increases, the reaction favors the products and shifts to the right, resulting in an increase in K.
Re: Effect of Temp. on K constant
for exothermic reaction, when the temp increases, equilibrium shifts to reactants (left) to decrease K
-for endothermic reactions: when temp increases, equilibrium shifts to products (right) to increase k
-for endothermic reactions: when temp increases, equilibrium shifts to products (right) to increase k
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Re: Effect of Temp. on K constant
Hi! I like to think of this in terms of Le Chatelier's principle. If you increase the temperature of an exothermic reaction, the reaction will shift towards the reactant side. This means that the reverse reaction rate will be increased. K (overall) will decrease as such. I hope this helps!
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