What is the true solution? Give an example.

Hint: There are three types of solutions, one is true solution, another is colloidal solution and the last one is suspension. All three types of solutions exist in nature and we counter them almost every day of our life.

Complete answer:
A true solution is a solution in which the solute gets completely dissolved into the solvent. A true solution is stable as a result of complete dissolution of solute in solvent. If the solute is not completely dissolved into the solvent, then it is not called a true solution.
Several examples of true solutions are there in nature as well as in our daily life, such as simple sugar in water, salt in water, air, acetic acid in water, ethanol in water, lemon juice, etc.
It is easy to determine whether a solution is a true solution or not, if in the solution we can see particles floating around, then it is not a true solution. Also, the particles dissolved in a true solution cannot be filtered out with a filter paper.
The other two types of solutions are colloidal solution and suspension. The criteria separating the three types of solution is the size of the particles of the solution. Size of particles of true solution is always less than 1 nanometer.
The size of particles in a colloidal solution is between 1 to 100 nanometers, and that of a suspension is more than 100 nanometers.

Note:
Another criteria for a true solution is that it does not show Tyndall effect, while the other two that are colloidal solution and suspensions show Tyndall effect. Also, the visibility of the solute particles in solvent are only visible in suspension, so it is necessary to check whether the solution is colloidal or not.