Which of the following is a physical property of matter?

• A. Reactivity with acid
• B. Melting point
• C. Ability to rust
• D. Flammability

Answer: (B)

Verified step by step guidance

1. Understand the difference between physical and chemical properties: Physical properties can be observed or measured without changing the substance's identity, while chemical properties describe how a substance interacts with other substances, resulting in a chemical change.
2. Review each option and classify it as physical or chemical property:
3. - Reactivity with acid: This describes how a substance chemically reacts with acid, so it is a chemical property.
4. - Melting point: This is the temperature at which a substance changes from solid to liquid without changing its chemical identity, so it is a physical property.
5. - Ability to rust and Flammability: Both involve chemical changes (oxidation and combustion respectively), so they are chemical properties.