A chemical change creates a new substance.

• A. Changes only color
• B. Changes only the state of matter
• C. Can be reversed easily
• D. Creates a new substance

Answer: (D)

Chemical changes involve breaking and forming bonds so that the substance’s composition changes and a new substance with different properties appears. The statement highlights this defining outcome: a chemical change creates a new substance. That’s why this option is the best. The other ideas describe physical changes, which don’t create new substances: changing color or changing the state of matter can happen without altering what the material is, and being easily reversible isn’t a reliable indicator since many chemical changes aren’t easily reversible either (for example, burning). A familiar example is rust forming iron oxide—the result is a new substance, clearly showing a chemical change.