Exothermic vs. Endothermic
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Exothermic vs. Endothermic
If a reaction has activation energy, is it always endothermic? If not, is it because deltaG plus the activation energy is still less than zero? or is there something else?
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Re: Exothermic vs. Endothermic
All reactions use activation energy, but exothermic reactions just produce more energy than they consumed. So to answer your question, having activation energy does not declare a reaction being endothermic vs exothermic. They could have the same Ea, but they depend on the initial and final energy use. Exothermic has a negative G, while endothermic has a positive G.
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Re: Exothermic vs. Endothermic
An endothermic reaction has a higher energy barrier in the forward direction so k forward is greater than k reverse which means that if you heated up a endothermic reaction the k forward would increase so the K overall would also increase and products would be favored
For an exothermic reaction, the activation energy is lower in the forward direction so if you heat up an exothermic reaction k reverse will increase which will result in a lower K and the reaction will favor reactants
For an exothermic reaction, the activation energy is lower in the forward direction so if you heat up an exothermic reaction k reverse will increase which will result in a lower K and the reaction will favor reactants
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Re: Exothermic vs. Endothermic
Both endothermic and exothermic reactions have Ea, however endothermic reactions will have a larger energy barrier to go over.
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Re: Exothermic vs. Endothermic
a reaction is endothermic is the E(a) (activation energy) of the forward reaction is higher than the reverse reaction. therefore, if the temperature increases, the rate constant of the forward reaction will increase because k is dependent on temperature.
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Re: Exothermic vs. Endothermic
Every reaction has activation energy since it is the minimum amount of energy needed to be able to undergo the reaction. Activation energy is the difference in the energy between the transition state and the reactants.
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Re: Exothermic vs. Endothermic
An exothermic reaction- the activation energy is lower in the forward direction so if you heat up an exothermic reaction k reverse will increase which will result in a lower K and the reaction will favor reactants
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Re: Exothermic vs. Endothermic
All reactions will have some sort of activation energy. What determines if a reaction is exothermic or endothermic is the final value of the amount of energy still within the system.
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Re: Exothermic vs. Endothermic
Endothermic and exothermic reactions both have an activation energy. But for endothermic reactions, the products have higher energy than the reactants and for exothermic reactions, the products have lower energy than the reactants.
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