Which of the following is a chemical change?

• A. Rusting of iron
• B. Dissolving sugar in water
• C. Melting of ice
• D. Breaking a glass

Answer: (A)

Verified step by step guidance

1. Understand the difference between physical and chemical changes. A physical change affects the form of a substance but not its chemical composition, while a chemical change results in the formation of one or more new substances with different properties.
2. Analyze each option to determine if it involves a change in chemical composition:
3. Dissolving sugar in water is a physical change because the sugar molecules disperse but do not chemically alter.
4. Melting of ice is a physical change because water changes from solid to liquid without changing its chemical identity (H\_2O remains H\_2O).
5. Breaking a glass is a physical change because the glass is physically fragmented but its chemical composition remains the same.
6. Rusting of iron is a chemical change because iron reacts with oxygen and moisture to form a new substance, iron oxide, which has different chemical properties.