A solution of salt in 100 g of water that still dissolves more solute at a given temperature is classified as:

• A. unsaturated
• B. supersaturated
• C. dilute
• D. saturated

Answer: (A)

This question tests solubility at a fixed temperature. Each solvent has a limit for how much solute can dissolve at that temperature. If more solute can still dissolve, the solution hasn’t reached that limit yet, so it is unsaturated. A saturated solution is at the maximum amount that can dissolve under those conditions. A supersaturated one contains more dissolved solute than the normal limit and is not typical under ordinary conditions. A dilute solution refers to a low concentration but doesn’t specify whether more solute can be added; the key clue here is the ability to dissolve more solute, which makes it unsaturated.