The term for the phenomenon of chemical change in the composition of matter is chemical reaction. This process involves the breaking and forming of chemical bonds, resulting in the transformation of reactants into products with different chemical properties. Chemical reactions are fundamental to all biological processes, including metabolism, respiration, and photosynthesis. They can occur in various environments under different conditions, and understanding these reactions is crucial for fields such as chemistry, biochemistry, and environmental science, impacting both theoretical research and practical applications.