Which of the following tests is used to detemine whether a solution containing a salt is saturated?
a add a crystal of the same salt to the solution
b cool the solution rapidly to see if crystals will be formed
c heat the solution until it boils
d stir the solution vigorously
When a solution is saturated it means that the given volume of solvent cannot dissolve any more quantity of the solute.
To test if a solution is saturated we add a crystal of the same salt to the solution. Three things can happen when this is done: the crystal dissolves in the solution, there is no change in the state of the crystal, the crystal grows larger. If the crystal dissolves in the solution it shows that the solution was unsaturated and the solvent could accommodate more of the solute. If the crystal grows larger in size it shows that the solution was super saturated, that lead to the solute separating and depositing on the crystal. If the crystal undergoes no change it shows the solution is saturated and can accommodate no more of the solute.
The correct answer is option A, add a crystal of the same salt to the solution.