Which of the following is NOT an example of a chemical change?

• A. Digestion of food
• B. Burning of wood
• C. Rusting of iron
• D. Melting of ice

Answer: (D)

Verified step by step guidance

1. Understand the difference between a chemical change and a physical change. A chemical change results in the formation of new substances with different properties, while a physical change affects the form or state of a substance without changing its chemical identity.
2. Analyze each option to determine if it involves a chemical change: Digestion of food involves breaking down molecules into new substances, so it is a chemical change.
3. Burning of wood produces new substances such as ash, carbon dioxide, and water vapor, indicating a chemical change.
4. Rusting of iron forms iron oxide, a new compound, which is a chemical change.
5. Melting of ice changes water from solid to liquid state without altering its chemical composition (H2O remains H2O), so it is a physical change and NOT a chemical change.