Final answer:
To determine the saturation status of a sodium thiosulfate solution, add solid sodium thiosulfate to see if it dissolves, or check for crystallization in a supersaturated solution. Quantitatively, compare the ion product with the solubility product. A solubility curve can also be utilized for this purpose.
Step-by-step explanation:
To determine whether a solution of sodium thiosulfate, Na2S2O3, is unsaturated, saturated, or supersaturated, you can add a small amount of solid sodium thiosulfate to the solution. If it dissolves, the original solution was unsaturated. If it does not dissolve, the original solution was saturated.
For a solution that is believed to be supersaturated, you can induce crystal formation by introducing a seed crystal or scratching the surface of the container to see if the excess solute precipitates. Additionally, comparing the ion product Qs with the solubility product Ksp can provide a quantitative measure of the saturation level.
A solubility curve can also be used to determine the saturation status of a solution by comparing the amount of solute in the solution to the maximum solubility indicated by the curve for the given temperature.