Which of the following statements best describes a compound?

• A. A substance composed of two or more elements chemically combined in fixed proportions.
• B. A pure substance consisting of only one type of atom.
• C. A solution in which the solute is evenly distributed throughout the solvent.
• D. A mixture of two or more substances that can be separated by physical means.

Answer: (A)

Verified step by step guidance

1. Understand the definition of a compound in chemistry: A compound is a pure substance formed when two or more different elements are chemically bonded together in a fixed ratio.
2. Compare this with other options: A pure substance consisting of only one type of atom describes an element, not a compound.
3. Recognize that a solution where the solute is evenly distributed throughout the solvent is a homogeneous mixture, not a compound.
4. Identify that a mixture of two or more substances separable by physical means is a mixture, not a compound, because compounds require chemical bonding.
5. Conclude that the best description of a compound is: 'A substance composed of two or more elements chemically combined in fixed proportions.'