What is the basic difference between exergonic and endergonic reactions? Group of answer choices Exergonic reactions release energy; endergonic reactions absorb it. In exergonic reactions, the reactants have less chemical energy than the products; in endergonic reactions, the opposite is true. Exergonic reactions involve the breaking of bonds; endergonic reactions involve the formation of bonds. Exergonic reactions involve ionic bonds; endergonic reactions involve covalent bonds.