Which of the following statements must be true of a catalyst in a reaction mechanism? I. Is consumed in an elementary step. II. Is regenerated in an elementary step after it is consumed. III. Is included in the overall balanced reaction equation.

I. Is consumed in an elementary step. II. Is regenerated in an elementary step after it is consumed

Explanation:

A catalyst as a substance is added to the reaction to increase the rate of the reaction without getting consumed in the process and this is done by replacement of the active energy and replacing of the reaction mechanism and enzymes are proteins that can act as the catalysts of the biochemical reactions. As a specie, the catalyst needs to be present at the beginning of the reaction and an intermediate is not present in the beginning and forms a reaction were it firms and disappears at the end. Thus gets consumed in the elementary step and is regenerated after it's consumed.