The zig-zag movement of dispersed phase particles in a colloidal system is known as

Options

A. Brownian motion
B. translational motion
C. circular motion
D. linear motion.

Explanation

To solve the question regarding the zig-zag movement of dispersed phase particles in a colloidal system, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the specific term used to describe the zig-zag movement of particles in a colloidal system.

2. **Identifying the Movement**: In colloidal systems, particles are not stationary; they exhibit random motion. This type of movement is characterized by a zig-zag pattern.

3. **Recognizing the Term**: The specific term used to describe this zig-zag movement is known as "Brownian motion." This term is named after the botanist Robert Brown, who observed this phenomenon in pollen grains suspended in water.

4. **Evaluating Other Options**: The question may provide multiple-choice answers. We can evaluate the other options:
- **Translational Motion**: This refers to the movement of an object from one point to another, which does not describe the zig-zag pattern.
- **Circular Motion**: This describes movement along a circular path, which is also not applicable here.
- **Linear Motion**: This refers to movement in a straight line, which again does not match the zig-zag description.

5. **Conclusion**: Based on the understanding and evaluation of the options, the correct answer to the question is "Brownian motion."

### Final Answer:
The zig-zag movement of dispersed phase particles in a colloidal system is known as **Brownian motion**.

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