Chapter 23, Problem 85A

Interpretation Introduction

Interpretation: To explain how the concentration of a saturated solution remains constant during the continuous dissolving of the undissolved solute.

Concept Introduction: A solution that has a greater amount of dissolved substance at certain conditions of temperature and pressure, then it is said to be a saturated solution. The saturated solution will be left in contact with the undissolved solute until there is no change in the concentration of the solution.

Answer to Problem 85A

A saturated solution contains solute in greater amounts so even though it is in contact with the undissolved solute there will be no change in the concentration of the solution.

Explanation of Solution

A saturated solution is already saturated with solute and at a certain temperature and pressure, the solute will not dissolve in the solution further. Therefore, even though the undissolved solute dissolves continuously there will be no change in the concentration of the solution. All the undissolved solute that is continuously dissolving will settle at the bottom of the solution.

Conclusion

The solubility of the solute will also depend on the state of the solute. If the solute is finely divided then there will be a greater solubility. The maximum amount of solute will be dissolved to make the solution saturated and further addition of the solute will not contribute to the saturation of the solution.