Which of the following is NOT a chemical change?

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

Answer: (C)

Verified step by step guidance

1. Step 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. Step 2: Analyze each option to determine if it involves a chemical change or a physical change:
3. Step 3: Rusting of iron involves iron reacting with oxygen to form iron oxide, which is a new substance, so it is a chemical change.
4. Step 4: Burning of wood involves combustion, producing new substances like carbon dioxide and ash, so it is a chemical change.
5. Step 5: Melting of ice is a change from solid to liquid water, which does not produce a new substance, so it is a physical change and therefore NOT a chemical change.