Advanced Placement (AP) Chemistry Practice Exam 2026 – All-in-One Guide to Exam Success!

When bonds are formed during a chemical reaction, energy is released. This process is tied to the stability of the molecules involved. When atoms or molecules come together to form new bonds, they reach a lower energy state compared to their separate, unbonded states. The energy that is released when these new bonds are formed can be understood through the concept of bond energies—the amount of energy released when bonds in the products are formed is greater than the energy needed to break the bonds in the reactants.

This release of energy often manifests as heat, which can lead to an increase in temperature in the surrounding environment, highlighting the exothermic nature of many reactions that form bonds. Therefore, when analyzing the overall energy changes in chemical reactions, the formation of bonds is a crucial step that contributes to the energy dynamics of the reaction, leading to the conclusion that energy is released during this process.