A chemical reaction is a process where one or more substances, known as reactants, undergo a transformation to produce new substances, called products. During a chemical reaction, the arrangement of atoms is altered, leading to the formation or breaking of chemical bonds. This transformation involves the conversion of reactant molecules into different chemical species with distinct properties. The reaction is governed by the principles of conservation of mass and energy, indicating that the total mass and energy of the system remain constant. Chemical reactions are crucial in understanding and explaining various natural and synthetic processes occurring in biological, industrial, and environmental contexts.