Which statement best describes a physical change?

• A. It changes the chemical composition of a substance.
• B. It forms new substances with new properties.
• C. It is not a physical change.
• D. It changes the substance's form or appearance without changing its identity.

Answer: (D)

A physical change happens when matter changes its form or appearance without changing what the substance actually is. For example, ice turning into liquid water changes from solid to liquid, but the substance is still water (H2O) with the same identity—no new substance forms. That’s why the statement describing changing the form or appearance without changing the substance’s identity is the best description of a physical change.

The other ideas describe chemical changes, where the substance’s composition changes and new substances with new properties are formed. And saying it’s not a physical change isn’t correct because many everyday changes, like cutting or melting, are physical changes.