$(a)$ Give any one point of difference between true solution,colloidal solution,and suspension.
$(b)$ $20 \, g$ of sodium chloride is dissolved in $100 \, mL$ of water. How will you test whether the given solution is saturated or unsaturated at the given temperature?
$(c)$ Suggest any one method by which we can increase the solubility of saturated solutions.

(N/A) The difference based on particle size is as follows:

Type of Mixture	Particle Size
True Solution	$< 1 \, nm$
Colloidal Solution	$1 - 100 \, nm$
Suspension	$> 100 \, nm$

$(b)$ To test if the solution is saturated or unsaturated,add a small amount of additional sodium chloride to the solution at the same temperature. If the added salt dissolves,the original solution was unsaturated. If the added salt does not dissolve and settles at the bottom,the original solution was saturated.
$(c)$ The solubility of most solid solutes in a liquid solvent increases with an increase in temperature. Therefore,by heating the solution,we can increase the solubility and dissolve more solute.