Tyndall effect in colloidal solution is due to

Options

A. Reflection of light
B. Refraction of light
C. Scattering of light by dispersed phase
D. Scattering of light by dispersion medium

Answer

**Step-by-Step Solution:**

1. **Understanding the Tyndall Effect**: The Tyndall effect is a phenomenon observed when light is scattered by particles in a colloidal solution. It is important to recognize the role of the dispersed phase and the dispersion medium in this effect.

2. **Identifying the Components**:
- **Dispersion Medium**: This is the continuous phase in which the colloidal particles are dispersed.
- **Dispersed Phase**: These are the small particles that are suspended in the dispersion medium.

3. **Mechanism of the Tyndall Effect**:
- When a beam of light passes through a colloidal solution, the particles of the dispersed phase scatter the light in different directions.
- If you observe the solution from a 90-degree angle to the direction of the light beam, you will see a visible path of light due to this scattering.

4. **Correct Answer Identification**:
- The Tyndall effect is specifically due to the scattering of light by the dispersed phase particles. Therefore, the correct option is **C: Scattering of light by the dispersed phase**.

5. **Conditions for the Tyndall Effect**:
- **Size of Particles**: The diameter of the dispersed particles should not be much smaller than the wavelength of the incident light. This ensures that the particles are large enough to scatter the light effectively.
- **Refractive Indices**: There must be a significant difference in the refractive indices of the dispersed phase and the dispersion medium. If the refractive indices are similar, scattering will not be observed.

6. **Conclusion**: The Tyndall effect is a clear demonstration of the scattering of light by the dispersed phase in colloidal solutions, making option C the correct answer.

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