in the preparation of the unknown compound 1 g of powdered charcoal was used as a catalyst for the reaction. what is the purpose of a catalyst in a chemical reaction

A catalyst is a substance that increases the rate of a reaction by lowering the activation energy. It does so by providing an alternative reaction pathway. The catalyst may react to form an intermediate with the reactant, but it is regenerated in a subsequent step so it is not consumed in the reaction. A catalyst speeds up a reaction by providing a set of elementary steps with more favorable kinetics than those that exist in its absence.