If a chemical reaction uses up energy the reaction is? A. limiting B. a product C. endothermic D. exothermic.

The reaction is endothermic if a chemical reaction uses up energy. There are two types of chemical reaction based on the energy usage which is the endothermic and the exothermic reaction. The endothermic reaction process is a chemical reaction that absorbs and uses the energy of its surrounding. The exothermic reaction is a chemical reaction process which releases the energy to its surrounding.