The origin of energy liberated in an exothermic reaction is primarily due to the potential energy stored in molecular bonds. In these reactions, more bonds are formed than broken, resulting in a net release of energy. Bond-making processes are exothermic, contrasting with bond-breaking, which requires energy input. A practical example is the dissolution of sulfuric acid in water, where the reaction releases significant heat due to the formation of stronger bonds in the aqueous solution, indicating a more stable state. In biological systems, the cleavage of phosphorus-oxygen bonds in molecules like ATP releases substantial energy, highlighting the role of exothermic reactions in energy transfer and storage.
