Brownian movement is found in

Options

A. Colloidal sol
B. Solid suspensions
C. True solution
D. Unsaturated fatty acids

Answer

### Step-by-Step Solution:

1. **Understanding Brownian Movement**:
Brownian movement refers to the random and erratic motion of microscopic particles suspended in a fluid (liquid or gas). This phenomenon is observed under a microscope and is a result of collisions between the suspended particles and the molecules of the fluid.

2. **Identifying the Conditions for Brownian Movement**:
For Brownian movement to occur, there must be two distinct phases:
- **Dispersed Phase (dp)**: This is the phase that consists of the particles being observed (e.g., colloidal particles).
- **Dispersion Medium (dm)**: This is the fluid in which the dispersed phase is suspended.

3. **Colloidal Solutions**:
Brownian movement is primarily observed in colloidal solutions. In these solutions, the dispersed particles are small enough to be affected by the random motion of the molecules in the dispersion medium, leading to the zigzag motion characteristic of Brownian movement.

4. **True Solutions vs. Suspensions**:
- In **true solutions**, the solute particles are too small to observe and do not exhibit Brownian movement because they are completely dissolved and do not have a distinct dispersed phase.
- In **suspensions**, the particles are too large, and while they may settle out of the medium, they do not exhibit the random motion characteristic of Brownian movement.

5. **Conclusion**:
Brownian movement is found in colloidal solutions, where the dispersed phase is small enough to be influenced by the surrounding fluid molecules, leading to the observable zigzag motion.

### Final Answer:
Brownian movement is found in colloidal solutions.

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