Which of the following statements is INCORRECT for colloid? 

The correct answer is Colloid is a homogeneous mixture..

Key Points

• Colloids are mixtures where one substance is dispersed evenly throughout another but the substances do not chemically combine.
• They are heterogeneous mixtures because the different components can be observed separately at the microscopic level.
• Colloidal particles are capable of scattering light due to the Tyndall effect.
• Colloidal particles are stable and do not settle down when left undisturbed.

Additional Information

• Tyndall Effect:
  • The scattering of light by particles in a colloid or particles in a very fine suspension.
  • This effect is used to distinguish between a colloid and a true solution.
• Types of Colloids:
  • Sol: Solid particles in a liquid (e.g., paint).
  • Gel: Liquid particles in a solid (e.g., jelly).
  • Aerosol: Liquid or solid particles in a gas (e.g., fog, smoke).
  • Emulsion: Liquid particles in another liquid (e.g., milk).
• Brownian Motion:
  • The random movement of colloidal particles as they are bombarded by molecules of the dispersion medium.
  • It helps in stabilizing the colloidal system by preventing the particles from settling down.
• Applications of Colloids:
  • Used in medicines, food industry, and various industrial processes.
  • Examples include blood (a colloid), whipped cream, and photographic films.