In a laboratory experiment, a solution is prepared by dissolving as much solute as possible in a solvent at a given temperature. Before a crystal of the solute is added to this solution, which term best describes the solution?

• A. Supersaturated
• B. Dilute
• C. Unsaturated
• D. Saturated

Answer: (D)

Verified step by step guidance

1. Understand the definitions of the terms related to solution concentration: an unsaturated solution can dissolve more solute, a saturated solution contains the maximum amount of solute dissolved at a given temperature, a supersaturated solution contains more solute than the saturation point (usually unstable), and a dilute solution has a relatively low concentration of solute.
2. Recognize that the problem states the solution is prepared by dissolving as much solute as possible at a given temperature, meaning no more solute can dissolve under those conditions.
3. Since the solution holds the maximum amount of solute that can dissolve at that temperature, it is at equilibrium between dissolved solute and undissolved solute.
4. Before adding a crystal of solute, the solution is exactly at this equilibrium point, which is the definition of a saturated solution.
5. Therefore, the term that best describes the solution before adding a crystal is 'saturated'.