Which of the following is a chemical property of rubbing alcohol (isopropanol)?

• A. It is flammable and can combust in air.
• B. It is colorless.
• C. It has a boiling point of 82 °C.
• D. It evaporates quickly at room temperature.

Answer: (A)

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, leading to a change in its chemical composition.
2. Analyze each option to determine if it describes a physical or chemical property: 'It is colorless' describes appearance (physical), 'It has a boiling point of 82 °C' describes a phase change temperature (physical), 'It evaporates quickly at room temperature' describes a physical change related to volatility (physical).
3. Identify the option that involves a chemical change: 'It is flammable and can combust in air' describes the ability of isopropanol to react with oxygen and undergo combustion, which changes its chemical structure, thus a chemical property.
4. Conclude that the chemical property of rubbing alcohol (isopropanol) is its flammability and ability to combust, as this involves a chemical reaction and change in composition.
5. Remember that chemical properties are often observed during chemical reactions, such as combustion, oxidation, or acid-base reactions, which alter the substance's identity.