Which of the following substances can only be separated into its components by a chemical reaction?

• A. Compound
• B. Solution
• C. Mixture
• D. Element

Answer: (A)

Verified step by step guidance

1. Understand the definitions of the terms: An element is a pure substance consisting of only one type of atom and cannot be broken down into simpler substances by chemical or physical means.
2. A mixture is a physical combination of two or more substances where each substance retains its own chemical identity and can be separated by physical methods such as filtration, distillation, or evaporation.
3. A compound is a pure substance formed when two or more elements chemically combine in fixed proportions. Compounds can only be separated into their individual elements or simpler compounds by chemical reactions, not by physical means.
4. Analyze the question: Since the question asks which substance can only be separated into its components by a chemical reaction, consider that elements cannot be broken down further, mixtures can be separated physically, and compounds require chemical reactions for separation.
5. Conclude that the correct answer is a compound because it requires a chemical reaction to break the chemical bonds between its elements to separate it into its components.