Answer:
The solutions are classified according to their ability to scatter light rays.
We can't just use this property because some true solutions also contain undissolved solute.
Step-by-step explanation:
Tyndall effect refers to the ability of a solution to scatter light rays. True solutions do not scatter light rays while false solutions scatter light rays.
Colloid particles are not large enough to be seen with naked eyes unlike suspensions. We should not confuse a colloid with a suspension because in a suspension, the dispersed solutes are seen with naked eye.