Energy Level Diagrams
In Exothermic Reactions...
- /\H is negative
- The products are at a lower energy than the reactants.
- The height difference represents the energy given out per mole.
- The initial rise represents the energy needed to break the old bonds.
In Endothermic Reactions...
- /\H is positive
- The products are at a higher temperture than the reactants.
- The difference in height represents the energy taken in during the reaction.
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What is Activation Energy?
- It is the initial energy given out that is used to break the bonds of the reactants.
- It represents the minimum energy needed for the reaction to happen.
- It is only shown on the energy diagrams for exothermic reactions.
Activation Energy and Cataysts:
- Catalysts lower the activation energy because it provides an alternative reaction pathway.
- This is shown by the lower curve on the graph because less initial energy is needed for the reaction to happen.
- The overall enthalpy change remains the same even with a catalyst.
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