A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. The particles in suspensions are bigger than 100 nm to 200 nm across. The particles of a suspension may not be visible to the naked eye but are visible under a microscope. Such as: Milk of magnesia is a suspension of magnesium hydroxide in water.


  • Suspensions are heterogeneous systems.
  • They stay only for a limited period. i.e. these are not stable as the particles have a tendency to settle down under the influence of gravity.
  • The particles of a suspension can neither pass through ordinary filter paper nor through animal membranes. Examples of suspensions are sodium chloride in benzene, turmeric in water, silver chloride, barium sulphate or sand in water.