Which shows one example of a physical change and one example of a chemical change?

• A. Dissolving Powder and Shredding Paper
• B. Freezing Water and Burning Coal
• C. Boiling Water and Melting Wax
• D. Rusting Iron and Baking a Cake

Answer: (D)

Physical changes alter how a substance looks or feels without forming a new substance, while chemical changes produce new substances with different properties. Freezing water is a physical change because it changes from liquid to solid without creating a new substance. Burning coal is a chemical change because it reacts with oxygen to form new substances like carbon dioxide and ash. This pairing clearly shows one physical and one chemical change in the same option. The other pairings either show two physical changes or two chemical changes, so they don’t meet the requirement as clearly.