If the reaction was an exothermic one; the energy is given out by the overall reaction. Therefore the products will have a lesser energy than the reactants.This can be represented in a energy profile as follows
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| Energy profile diagram for exothermic reaction |
- Activation energy is the energy barrier for the reactants to become products.In an energy profile it can be represented by an arrow from the reactants to the peak
- Enthalpy change is from reactants to the products.
- Energy profile can also be represented with real energy values and the names of the reactants and products
Endothermic reactions will have a different energy profile than the exothermic one because in endothermic reactions overall energy change is absorption of heat. The products will have a higher energy than the reactants.
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| Energy profile for endothermic reaction |
