Which of the following is a characteristic of a solution?

• A. It consists of only one pure substance.
• B. It always contains visible particles that can be filtered out.
• C. It separates into layers upon standing.
• D. It is a homogeneous mixture of two or more substances.

Answer: (D)

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 a solution consists of two or more substances, typically a solute dissolved in a solvent, rather than being a single pure substance.
3. Recognize that solutions do not have visible particles that can be filtered out; the solute particles are at the molecular or ionic level and are evenly distributed.
4. Note that solutions do not separate into layers upon standing because the solute remains dissolved in the solvent, maintaining uniformity.
5. Conclude that the key characteristic of a solution is that it is a homogeneous mixture of two or more substances.