Which statement best defines an aqueous solution?

• A. Contains water as the solvent.
• B. A mixture of water and solute with a chemical reaction.
• C. A substance with a pH of 7.
• D. A substance that cannot dissolve anything.

Answer: (A)

An aqueous solution is a homogeneous mixture in which water is the solvent. Water’s polarity lets many dissolved substances disperse uniformly by surrounding ions or molecules, forming a stable solution. The key point is that water is the dissolving medium used for the dissolved substance to become part of the solution.

This makes the statement the best definition: it focuses on water being the solvent. Dissolving can happen without any chemical reaction, so requiring a reaction isn’t part of the defining idea. The pH value isn’t what defines an aqueous solution, since aqueous solutions can be acidic, neutral, or basic depending on the solute. And the notion that nothing can dissolve anything contradicts what an aqueous solution is, since dissolution in water is exactly what defines it.