Chemical reactions involve thermal energy changes, with exothermic and endothermic reactions reflecting energy release and absorption, respectively.
During chemical reactions, thermal energy is absorbed and/or released, resulting in a change in temperature. Total energy absorbed to break bonds minus total energy released when new bonds form represents the energy changes in a chemical reaction.
Chemical reactions that release energy are termed exothermic reactions, such as the combustion of methane gas. On the other hand, reactions that absorb energy are known as endothermic reactions, like photosynthesis.
Enthalpy change (ΔH) reflects the energy absorbed or released in the form of heat in reactions, correlating with the internal energy change (ΔG) in most reactions.
https://brainly.com/question/34137415