What is a solution?

A solution is defined as a homogeneous mixture formed when one substance dissolves another. In the context of solutions, the substance that gets dissolved is known as the solute, while the substance that does the dissolving is referred to as the solvent. This process results in a uniform composition throughout, meaning that any sample taken from the solution will have the same concentration of solute and solvent.

The other options do not accurately represent the concept of a solution. While a mixture of solids may occur, it does not constitute a solution because it lacks a dissolving solvent. A combination of liquids can occur in various forms, but without one liquid dissolving in another, it does not qualify as a solution. Lastly, a compound results from a chemical reaction forming bonds between atoms, which is distinct from the physical process of dissolving that characterizes solutions. Therefore, the correct understanding of what constitutes a solution is pivotal in the study of chemistry and is particularly relevant when considering pesticide formulations and applications.