In styrene foam , the dispersed phas and dispersion medium are respectively :

Options

A. Gas, gas
B. Solid, solid
C. Gas, solid
D. None of these

Answer

To solve the question regarding the dispersed phase and dispersion medium in styrene foam, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Styrene Foam**:
- Styrene foam is a type of colloid. Colloids consist of two phases: the dispersed phase and the dispersion medium.

2. **Identify the Phases**:
- In styrene foam, the dispersed phase is the gas that is trapped within the solid structure of the foam.
- The dispersion medium is the solid matrix that forms the structure of the foam.

3. **Classify the Type of Colloid**:
- Styrene foam can be classified as a solid foam, where the solid (styrene polymer) acts as the dispersion medium and the gas (usually air) is the dispersed phase.

4. **Select the Correct Option**:
- Based on the identification, we can conclude that in styrene foam, the dispersed phase is gas and the dispersion medium is solid.
- Therefore, the correct option is option 3: gas (dispersed phase), solid (dispersion medium).

### Final Answer:
The dispersed phase and dispersion medium in styrene foam are respectively: **gas and solid**.

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