4. Define the terms :(a) Saturated solution(b) Pure substance(c) Colloid(d) Suspension

(a) Saturated solution : A saturated solution is a solution in which the maximum amount of solute has been dissolved at a particular temperature. (b) Pure substance : Pure substance consist only one type of atoms or molecules or compounds. (c) Colloid : A colloid is heterogeneous mixture in which one substance is scattered as very fine particles in a continuous medium of another substance. These particles cannot be seen by naked eye. Example : Ink, Blood. (d) Suspension : A suspension is a heterogeneous mixture containing solid particles that are big enough to settle down. Particles of suspension are visible to the naked eye. Example : Chalk powder, Paints, etc.