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

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

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. Melting of ice is a physical change because it changes water from solid to liquid without altering its chemical structure (H\_2O remains H\_2O).
4. Breaking a glass is a physical change because it changes the shape and size of the glass but does not change its chemical composition.
5. Dissolving sugar in water is generally a physical change because sugar molecules disperse in water but do not chemically react to form new substances.
6. Rusting of iron is a chemical change because iron reacts with oxygen and moisture in the environment to form a new substance, iron oxide (rust), which has different chemical properties from iron.