Which of the following best describes a solution?

• A. A Homogeneous Mixture With Evenly Distributed Particles That Do Not Settle Out
• B. A Heterogeneous Mixture
• C. A Pure Substance
• D. A Chemical Reaction

Answer: (A)

A solution is a homogeneous mixture formed when a solute dissolves in a solvent, resulting in a uniform composition throughout. In a true solution, the particles are dispersed at the molecular level so you can’t see separate parts, and they stay evenly distributed over time. Because the solute is dissolved, there’s no distinct layer or separate phase that would settle out, even if the mixture sits undisturbed.

This description matches a solution and differentiates it from other possibilities. A heterogeneous mixture would have visible, separate parts that aren’t evenly distributed. A pure substance is made of only one kind of particle, not dissolved materials. A chemical reaction involves changing substances into new ones, not simply mixing to form a uniform solution.