Energy

What is energy? How is it involved in the rate of a reaction? Well, think of energy as the driving force behind all reactions. Reactions either require energy to make them work, or they give off energy. Take a look at this diagram:

We can see here that it takes a certain amount of energy before the reactants can ever combine and turn into products. If the reaction conditions supply this energy, then the reaction will proceed. Also, if you have products, you can reverse the reaction by the same means. In the graph above, it would take more energy to convert products to reactants than to convert reactants to products.

During a reaction, it takes energy to get over the activation energy hump. However, when the reaction proceeds down the "products slide," you can see that energy is given off, because you end the slide at a much lower energy level than when you started the slide. This energy might be given off in a wide variety of forms, such as kinetic, potential, heat, chemical, electrical, or light.

Catalysts work by decreasing the activation energy. This speeds up the reaction because it does not take as long to accumulate a smaller amount of energy.

Temperature is a measure of the amount of energy in a system.

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