What is a solution in the context of chemistry?

In chemistry, a solution refers specifically to a homogeneous mixture where one or more substances, known as solutes, are completely dissolved in another substance, called the solvent. This means that the resulting mixture has a uniform composition throughout; the solutes cannot be easily distinguished from the solvent.

For example, when table salt (sodium chloride) is dissolved in water, the sodium and chloride ions disperse evenly throughout the water, creating a saline solution. The properties of the solution, such as boiling point and electrical conductivity, can differ from those of the individual components, which highlights the significance of understanding solutions in chemical processes.

The other options do not accurately depict what a solution is. A solid mixture of substances describes a physical mixture rather than a solution. A reversible chemical reaction refers to reactions where reactants can form products and then revert back, which does not define a mixture. Lastly, a method for separating mixtures encompasses techniques like filtration or distillation, which do not focus on the uniformity and dissolved nature characteristic of solutions.