The s-block element used as a catalyst in the manufacture of buna-S rubber is

Options

A. Mg
B. Ca
C. Ba
D. Na

Answer

To determine the s-block element used as a catalyst in the manufacture of Buna-S rubber, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Buna-S Rubber**:
- Buna-S rubber is a type of synthetic rubber that is produced from the copolymerization of butadiene and styrene. The chemical structure of butadiene is represented as CH2=CH-CH=CH2, and styrene is represented as C6H5-CH=CH2.

2. **Identifying the Catalyst**:
- In the production of Buna-S rubber, a catalyst is required to facilitate the polymerization process. The options provided are magnesium, calcium, barium, and sodium.

3. **Analyzing the Options**:
- **Magnesium (Mg)**: While it is an s-block element, it is not commonly used in the production of Buna-S rubber.
- **Calcium (Ca)**: Also an s-block element, but not typically used as a catalyst in this process.
- **Barium (Ba)**: Another s-block element, but it is not known for its role in this specific rubber production.
- **Sodium (Na)**: Sodium is an s-block element that is known to be used as a catalyst in the polymerization of butadiene and styrene to produce Buna-S rubber.

4. **Conclusion**:
- Based on the analysis, the s-block element used as a catalyst in the manufacture of Buna-S rubber is **Sodium (Na)**.

### Final Answer:
The s-block element used as a catalyst in the manufacture of Buna-S rubber is **Sodium (Na)**.

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