Question

Why do the colloidal particles in a colloidal solution not aggregate together to form bigger particles and settle down? Explain

Answer 1

• Colloids are types of mixtures having dispersion medium and dispersed phase
• The 1-1000 nm-sized colloidal particles which are dispersed in a medium are called the dispersed phase and the medium in which particles are dispersed is called the dispersion medium
• Depending upon the states of the dispersed phase and dispersion medium, different colloids are present like emulsion, aerosol, sol, etc..
• Colloidal particles are in continuous motion so they will not settle down, when light passes through a colloidal solution path of light become visible and this phenomenon is called the Tyndall effect
• The zig-zag motion of colloidal particles in the dispersion medium is called Brownian movement
• Presence of charge causes the particles to move towards cathode and anode when emf applied and this is called electrophoresis

Therefore, due to the continuous zig-zag motion of colloidal particles and repulsion of similar charges on colloids (sols) prevent them aggregate together to form bigger particles and settle down