Question

Compare true solution, suspension, and colloids in terms of

(i) filterability

(ii) stability

Answer 1

Substances are classified into solution, colloids, and suspension depending upon the property of the particles-

True solution	Colloids	Suspension
The solute particles which are less than 1 nm in size are dissolved in the solvent.	The colloidal particles having 1-1000 nm size dispersed in the medium.	The particles which are having a size greater than 1000 nm are suspended in the medium.
The particles do not settle down on standing.	The particles do not settle down on standing but can be forced to settle down by the centrifugation method.	The suspended particles settle down on standing.
To separate the particles, we can't use filter paper.	To separate the particles, filter paper can not be used.	To separate the suspended particles, filter paper can be used.
Example: sugar solution.	Example: milk.	Example: sand in water.

(i) By analyzing the size of particles, particles of true solution and colloids can pass through the filter paper, whereas particles of suspension can not pass through the filter paper.

(ii) Since the particles of true solution and colloids do not settle down on standing, we can say that they are stable whereas suspension is unstable which settles on standing.