Which of the following is a chemical property of iron?

• A. Iron is malleable and can be shaped easily.
• B. Iron reacts with oxygen to form rust.
• C. Iron has a density of 7.87 g/cm^3.
• D. Iron is silver-gray in color.

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 a substance's ability to undergo chemical changes.
2. Analyze each statement to determine if it describes a physical or chemical property: For example, malleability, density, and color are physical properties because they describe how the substance looks or behaves without changing its composition.
3. Identify the statement that involves a chemical change or reaction: 'Iron reacts with oxygen to form rust' describes a chemical property because it involves iron undergoing a chemical reaction to form a new substance (rust).
4. Conclude that the chemical property of iron is its ability to react with oxygen to form rust, as this involves a change in the chemical composition of iron.
5. Remember that chemical properties are often observed during chemical reactions, whereas physical properties are observed without altering the substance's chemical identity.