Tyndall phenomenon is exhibited by

Options

A. NaCl solution
B. Starch solution
C. Urea solution
D. Fe`Cl_(3)` solution

Answer

**Step-by-Step Solution:**

1. **Understanding the Tyndall Phenomenon**: The Tyndall phenomenon, also known as the Tyndall effect, refers to the scattering of light by colloidal particles or very fine suspensions. This effect is observed when light passes through a colloidal solution.

2. **Identifying Colloidal Solutions**: Colloidal solutions consist of particles that range in size from 1 nanometer to 1000 nanometers. These particles are large enough to scatter light but small enough to remain suspended in the medium.

3. **Differentiating Between Solutions**: It is essential to differentiate between colloidal solutions and true solutions. True solutions, like a NaCl solution, have particle sizes less than 1 nanometer, which do not scatter light and therefore do not exhibit the Tyndall effect.

4. **Examples of Colloidal Solutions**: Common examples of colloidal solutions that exhibit the Tyndall effect include starch solutions and other heterogeneous mixtures. These solutions can scatter light effectively due to the presence of larger particles.

5. **Analyzing Other Solutions**: Solutions like urea and FeCl3 are homogeneous solutions. Urea does not form a colloidal solution, and FeCl3, being a strong electrolyte, dissociates into ions, forming a homogeneous solution that does not exhibit the Tyndall effect.

6. **Conclusion**: Based on the above analysis, the Tyndall phenomenon is exhibited by colloidal particles and very fine suspensions, while true solutions and certain electrolytes do not show this effect.

**Final Answer**: The Tyndall phenomenon is exhibited by colloidal solutions.

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