Question

Define the following terms.

Colloids

Answer 1

• Colloids are heterogeneous mixtures.
• A heterogeneous mixture is a mixture that is non-uniform and contains smaller parts.
• Every colloid contains two parts - colloidal particles (dispersed phase) and dispersing medium.
• The particles of colloids (solid or liquid) will have an intermediate size between suspension and solution particles.
• The particles of colloids do not dissolve but get dispersed in the medium and cannot be separated by filtration.
• The particles can scatter light due to the large size of the particles
• For instance, we can observe the light from car headlamps through the fog.

Examples of colloids:

• Milk (dispersed phase: liquid; dispersed medium: liquid)
• Fog (dispersed phase: solid; dispersed medium: gas.
• Insecticide sprays (dispersed phase: solid; dispersed medium: gas)