How can an unsaturated solution of a solid be made saturated?
a. increasing the temperature of the solvent
b. decreasing the temperature of the solvent
c. stirring the solution
d. removing solute

Option (b) is the correct answer.

Explanation:

A solution in which concentration of solute is lower than the equilibrium solubility is called an unsaturated solution.

Whereas a solution in which no more solute can be dissolved is known as a saturated solution.

Since solubility is proportional to temperature, therefore, decreasing the temperature will decrease the solubility. As a result, the solution will become saturated as on decreasing the temperature no more solute is soluble in the solution.

sodium (na), for example, has one electron in its valence shell. this is an unstable state because that valence shell needs eight electrons to be full. in order to fill its valence shell, find a way to add seven electrons to its valence shell

the answer is d.) potassium