what is an exothermic
Exothermic reaction. An exothermic reaction is a chemical reaction that releases energy by light or heat. It is the opposite of an endothermic reaction. Expressed in a chemical equation: reactants â products + energy. Exothermic Reaction means exo meaning releases and thermic means heat. So the reaction in which there is release of heat with or without light is called exothermic reaction.