Which of the following is an example of a chemical change?

Which of the following is an example of a chemical change?

• A. Ice melting.
• B. Iron rusting.
• C. Boiling water.
• D. Dissolving sugar in water.

Answer: (B)

Chemical changes happen when substances react to form new substances with different properties. Rusting is a classic example because iron reacts with oxygen (and water) to form iron oxide, a material with a different chemical composition and characteristics than the original iron. This isn’t just a change in appearance; a new substance with new bonds is created. The other options are physical changes: melting ice and boiling water involve changing state, not composition, and dissolving sugar in water keeps the sugar as the same substance, just dispersed. So the example of a chemical change is iron rusting.

Chemical changes happen when substances react to form new substances with different properties. Rusting is a classic example because iron reacts with oxygen (and water) to form iron oxide, a material with a different chemical composition and characteristics than the original iron. This isn’t just a change in appearance; a new substance with new bonds is created. The other options are physical changes: melting ice and boiling water involve changing state, not composition, and dissolving sugar in water keeps the sugar as the same substance, just dispersed. So the example of a chemical change is iron rusting.