What is a catalytic reaction?

A catalytic reaction is defined as one that is accelerated by the presence of a catalyst. A catalyst is a substance that increases the rate of a chemical reaction without being consumed or undergoing any permanent change itself. It does this by lowering the activation energy required for the reaction to proceed, allowing reactants to convert into products more quickly and efficiently.

In the context of organic chemistry, catalysts are widely used to drive reactions toward desired products under milder conditions or to favor certain pathways over others. This can be particularly important in synthesizing complex molecules or in industrial processes where efficiency is key.

The other answer choices do not accurately describe a catalytic reaction. For example, a reaction occurring without any external influence does not necessarily involve a catalyst; it simply happens spontaneously under certain conditions. A reaction involving multiple steps may or may not be catalytic, as it depends on the specific mechanisms and intermediates presented, and a reaction that produces heat is describing an exothermic process, which can occur with or without a catalyst. Thus, the essence of what makes a reaction catalytic is solely tied to the influence of the catalyst itself—hence, the reason for selecting the correct answer.