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Activation Energy
Activation Energy

Activation Energy

Author: Nathan Lampson

This lesson will explain how activation energy is needed to start a chemical reaction.

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The amount of energy required in order for molecules to chemically react with one another is called activation energy.

Certain chemical reactions require more energy than others to occur.  In order to speed up a chemical reaction, enzymes can lower the activation energy required for chemicals to react. An enzyme that lowers the activation energy of a reaction is called a catalyst.

This image shows the amount of energy required for a chemical reaction to occur with and without a catalyst.

Activation Energy