Tyndall effect: When the particles can scatter a beam of light passing through them and make the path of light visible, it is known as the Tyndall effect.
The light is scattered when light collides with the colloidal particles and deviates from its normal straight line path.
This scattering makes the path of the light beam visible, as illustrated below in comparison with solutions where the Tyndall effect is not observed.
Colloid: A colloid is a heterogeneous mixture in which the particles cannot be seen with the naked eye.
The diameter of the particles of colloids lies in the range of .
