Why does a catalyst cause a reaction to proceed faster?

Answer 1

It decreases the activation energy, or the energy barrier the reactants must go through to form products. This is the same thing as the energy of the transition state.

By decreasing the activation energy necessary for the reaction to occur, more reactants are able to form products since not as much energy is needed.

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Answer 2

A catalyst lowers the activation energy required for the reaction to occur, which allows the reaction to proceed faster at the same temperature. It does this by providing an alternative reaction pathway that is more favorable and requires less energy to reach the transition state.

Answer 3

A catalyst lowers the activation energy for a reaction between two molecules by providing an alternative path for the reaction to happen.

This way more molecules will collide with the correct amount of energy, hence speeding up the reaction.