Smoke is a dispersion of:

Options

A. A solid in gas
B. A gas in solid
C. A gas in gas
D. A liquid in gas.

Explanation

To solve the question "Smoke is a dispersion of:", we need to identify the components of smoke in terms of the dispersed phase and the dispersion medium.

### Step-by-Step Solution:

1. **Understanding the Components of Smoke**:
- Smoke is a mixture that contains tiny solid particles suspended in a gas.

2. **Identifying the Dispersed Phase**:
- In smoke, the tiny solid particles (like soot or ash) are the dispersed phase. This means that these solid particles are the ones that are distributed throughout the medium.

3. **Identifying the Dispersion Medium**:
- The gas that carries these solid particles is the dispersion medium. In the case of smoke, this gas is typically air.

4. **Classifying the Type of Dispersion**:
- Since we have solid particles dispersed in a gas, we classify this type of colloid as "solid in a gas." This is a specific type of colloid known as an aerosol.

5. **Conclusion**:
- Therefore, the correct answer to the question is that smoke is a dispersion of **solid in a gas**.

### Final Answer:
Smoke is a dispersion of **solid in a gas**.

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