Breaking and making bonds
Bond-breaking is an endothermic process. Energy is released when new bonds form. Bond-making is an exothermic process. Whether a reaction is endothermic or exothermic depends on the difference between the energy needed to break bonds and the energy released when new bonds form.
What bond does an exothermic reaction have?
In an exothermic reaction, the bonds in the product have higher bond energy (stronger bonds) than the reactants. In other words, the energy of the products is lower than the energy of the reactants, hence is energetically downhill, shown in Figure 7.5. 2B. Energy is given off as reactants are converted to products.
Is formation endothermic or exothermic?
Bond formation is an EXOTHERMIC process. Bond breaking (i.e. fission, cleavage) is an ENDOTHERMIC process.
