Definition
Chemical Energy
Chemical energy is the form of energy stored in the bonds of a molecule, released or absorbed when the bonds are rearranged in a chemical reaction. It is the potential energy of the electronic configuration: a function
of the positions of the constituent atoms and their electrons. Formally, for a reaction converting reactants
into products , The free-energy change
determines the direction: exergonic reactions ( ) release chemical energy, endergonic reactions ( ) require an input of energy.