unsaturated solution

An unsaturated solution is one that can still dissolve more solute at its current temperature.

• Adding the first few spoonfuls of salt to a glass of water keeps the solution unsaturated — every spoonful disappears completely, with nothing settling at the bottom.
• Whether a solution counts as unsaturated depends entirely on temperature: heating an unsaturated solution doesn't just keep it unsaturated, it actually raises how much more solute it can take before turning saturated.
• An unsaturated solution can become saturated simply by adding more solute, or as temperature changes, since solubility itself shifts with heat.
• Knowing whether a solution is unsaturated is useful well beyond the classroom — it's exactly the kind of judgment that decides whether a recipe, a medicine, or an industrial process can safely dissolve more of an ingredient.