Explain what obsserved i.when a beam of light is passed through a colloidal sol. ii.an electrolyte,NaCl is added to hydrated ferri oxide sol. iii.electic current is passed through a colloidal sol.

Explanation

i) Due to the presence of a paiticular type of electric charge, the colloidal particles present in the colloidal dispersion move towards a particular electrode under the influence of an electric field. This pluenomenori is called electropitoresis
it) When a beam of light is passed through a colloidal solution kept in dark ._+. the path of the beam gets illuminated with .a biutsti light. This phenomenon is called tyndall effect.