What defines a chemical solution?

A chemical solution is defined as a homogeneous mixture where one substance, known as the solute, is uniformly dissolved in another substance, known as the solvent. In this context, the correct choice describes a solution as one where the solute does not settle out and remains evenly distributed throughout the solvent. This characteristic ensures that every part of the solution has the same properties, making it consistent in composition and behavior.

This definition highlights the key characteristic of a chemical solution: the dissolution process that creates a stable mixture, which is essential in various chemical processes, including those involved in water treatment and other chemical applications. Solutions play a vital role in the behavior of substances in solution, affecting aspects like reaction rates and the ability to conduct electrical current.

The other options presented describe mixtures or characteristics that do not pertain to the definition of a chemical solution. For instance, a mixture containing both solid and liquid, or exclusively solids, does not meet the criteria of a homogeneous solution. Additionally, substances that do not dissolve in water do not form true solutions, as they remain separate from the solvent rather than being integrated into it. Therefore, only the description that emphasizes dissolution within a homogeneous mixture correctly defines a chemical solution.