A chemical change is a process in which one or more substances are transformed into one or more new substances with different properties through a chemical reaction. This involves the rearrangement of atoms and the breaking and forming of chemical bonds, resulting in products that differ chemically from the original reactants
. Key characteristics of a chemical change include:
- Formation of new substances with different chemical compositions and properties.
- Often accompanied by energy changes, such as heat being released (exothermic) or absorbed (endothermic).
- Indicators such as temperature change, color change, formation of gas bubbles, precipitate formation, light emission, or odor change.
- Typically irreversible by simple physical means, unlike physical changes which do not produce new substances and are usually reversible
Examples of chemical changes include burning wood, rusting iron, cooking an egg, digestion, and the reaction of baking soda with vinegar
. In summary, a chemical change is synonymous with a chemical reaction where reactants chemically transform into products with new chemical identities
