Which of the following is NOT a physical property?

• A. Color
• B. Ability to rust
• C. Density
• D. Boiling point

Answer: (B)

Verified step by step guidance

1. Step 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 a substance's ability to undergo chemical changes.
2. Step 2: Review each option to determine if it describes a physical or chemical property. Color, density, and boiling point are all physical properties because they can be observed or measured without altering the substance's chemical structure.
3. Step 3: Analyze 'Ability to rust.' Rusting is a chemical reaction where iron reacts with oxygen and moisture to form iron oxide, which changes the substance's chemical identity.
4. Step 4: Conclude that 'Ability to rust' is a chemical property because it involves a chemical change, unlike the other options which are physical properties.
5. Step 5: Therefore, the property that is NOT physical among the options is 'Ability to rust.'