Which of the following is a characteristic of a solution?

• A. Its components can be separated by filtration.
• B. It always contains a solid suspended in a liquid.
• C. It is a homogeneous mixture of two or more substances.
• D. It is always composed of a solute and a gas.

Answer: (C)

Verified step by step guidance

1. Understand the definition of a solution: A solution is a homogeneous mixture, meaning its composition is uniform throughout.
2. Recall that in a solution, the components are mixed at the molecular or ionic level, so they cannot be separated by simple physical methods like filtration.
3. Recognize that solutions can be in any phase combination (solid, liquid, gas), but they do not necessarily have a solid suspended in a liquid; that would be a suspension, not a solution.
4. Note that a solution always consists of at least two substances: a solute (the substance dissolved) and a solvent (the substance doing the dissolving), but the solvent is not limited to gases.
5. Conclude that the key characteristic of a solution is that it is a homogeneous mixture of two or more substances, which distinguishes it from suspensions and heterogeneous mixtures.