Question

How will you prepare a saturated solution of sodium chloride in water at $25°\mathrm{C}$? What will happen if this solution is cooled$10°\mathrm{C}$?

Answer 1

Preparing a saturated solution of sodium chloride at $25°\mathrm{C}$:

1. Bring the water to $25°\mathrm{C}$ and add keep on adding sodium chloride to it and stir it until no more sodium chloride can dissolve in it.
2. On cooling the water to$10°\mathrm{C}$, some of the sodium chlorides will be separated from the water by crystallization. This is because the solubility of solid decreases with a decrease in temperature.

About the Crystallization process:

1. Crystallization is a process used to separate a pure solid in the form of its crystals from a solution.
2. In this process, the solution is warmed in an open container allowing the solvent to evaporate.
3. As the saturated solution is allowed to cool the solid comes out of the solution as crystals and starts to grow.
4. An excellent and well-known example of the separation of salt from seawater.
5. The salt we get from seawater has many impurities in it. To remove these impurities, the process of Crystallization is used.