Question

What do you understand by a colloidal solution? Why do they show Tyndall effect?

Answer 1

In true solutions, the solute dissolves completely in the solvent at the molecular level, meaning that the solute particles are present at their molecular size i.e. well below the size of a particle required to exhibit light scattering dispersion (the Tyndall effect). On the othewr side, the particles in colloids, unlike those in most true solutions, are large enough to scatter visible light.

Answer 2

colloid is a heterogeneous mixture in which the size of particles in small than suspension and bigger than solution.
it shows Tyndall effect because its particles are quite larger