Which of the following statements best describes an element?

• A. An element is a substance that can be separated into its components by filtration.
• B. An element is a compound formed by the chemical combination of two or more atoms.
• C. An element is a mixture of two or more substances that can be separated by physical means.
• D. An element is a pure substance that cannot be broken down into simpler substances by chemical means.

Answer: (D)

Verified step by step guidance

1. Understand the definition of an element in chemistry: An element is a pure substance consisting of only one type of atom.
2. Recognize that elements cannot be broken down into simpler substances by chemical means, unlike compounds or mixtures.
3. Distinguish elements from compounds, which are substances formed by the chemical combination of two or more different atoms.
4. Differentiate elements from mixtures, which are physical combinations of two or more substances that can be separated by physical methods such as filtration.
5. Conclude that the best description of an element is that it is a pure substance that cannot be broken down into simpler substances by chemical means.