How Many Types of Colloids are There

Introduction

A colloid is a mixture of two substances with microscopically distributed particles suspended above each other. Particle sizes range from 0 to 1000 nanometers. This range is typically larger than particles found in solution. A mixture is classified as a colloid only if the particles of the mixture do not settle after being left alone. Colloidal solutions exhibit properties of the Tyndall effect, in which light rays are scattered on colloids due to interactions between light and colloidal particles.

Types of Colloids

A common method of classifying colloids is based on the phases in which they are dispersed and in which phase they are dispersed. Types of colloids include Solid sol, Sol, Aerosol, Gel, Emulsion, Aerosol, and Foam.

1. Sol is a colloidal suspension of solid particles in a liquid.
2. An emulsion is between two liquids.
3. Bubbles form when many gas particles are trapped in a liquid or solid.
4. Aerosols contain small liquid or solid particles dispersed in a gas.

When the dispersion medium is water, the colloidal system is often called a hydrocolloid. The dispersed phase particles can be in different phases depending on the amount of water available. For example, mix jello powder with water to make a hydrocolloid. A common use of hydrocolloids is in the manufacture of medical bandages.

Classification of Colloids

Colloids are mixtures of finely divided substances mixed with other substances. The substance dispersed in the solution is called the dispersed phase, and the solution in which the substance is dispersed is called the dispersion medium.
Based on the type of colloid, their classification is made. These are categorised as follows:
1. Multimolecular colloids
2. Macromolecular colloids
3. Associated colloids

Multimolecular Colloids

When the dispersed phase forms aggregates of a large number of atoms or small molecules, they form a kind of suspended particle within the dispersion medium, forming a polymolecular colloid. One of the best examples of this type is the sulphur molecule. They form species within the dispersion medium by associating multiple sulphur atoms of different types with each other.

Macromolecular Colloids

The macromolecules in this colloid are dispersed throughout the medium, forming a homogeneous mixture. Although relatively large, they remain within the size range required to form a colloidal solution. These colloidal systems are fairly stable and match the properties of solutions in many respects. The best examples of this type of colloidal solution are cellulose, enzymes, starches, etc. found in cells. This can be seen as an example of colloids in everyday life.

Associated Colloids

At low concentrations, some electrolytes behave like strong solutions. At high concentrations, it behaves like a colloidal system. At higher electrolyte concentrations, smaller particles physically associate to form larger particles. These aggregated particles are also called micelles. To give two examples of colloids in our daily lives, detergents and soaps are the best choices.