Define the term "Tyndall effect".

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Tyndall Effect**: The Tyndall effect is defined as the scattering of visible light by colloidal particles present in a medium. This scattering makes the path of light visible when it passes through a colloidal solution.

2. **Characteristics of Colloidal Solutions**: Colloidal solutions consist of particles that range in size from 1 to 1000 nanometers. These particles are suspended in a dispersion medium, which can be a liquid, solid, or gas.

3. **Example of Tyndall Effect**: A common example of the Tyndall effect can be observed when light passes through a colloidal solution like milk. In this case, the colloidal particles in the milk scatter the light, making the milk visible.

...