Natural rubber is vulcanized by heating it with

Options

A. carbon disulphide
B. sulphur
C. carbon black
D. zinc oxide

Answer

To solve the question "Natural rubber is vulcanized by heating it with," we need to understand the process of vulcanization and the materials involved.

### Step-by-Step Solution:

1. **Understanding Natural Rubber**:
- Natural rubber is primarily composed of polyisoprene, specifically in the cis configuration, which is known as cis-polyisoprene. It has low elasticity and tensile strength in its natural state.

2. **What is Vulcanization?**:
- Vulcanization is a chemical process that involves heating rubber with sulfur. This process improves the physical properties of rubber, such as elasticity and tensile strength.

3. **Role of Sulfur in Vulcanization**:
- When natural rubber is heated with sulfur, sulfur atoms form cross-links between the long polymer chains of rubber. These cross-links are primarily disulfide linkages, which stabilize the structure of the rubber.

4. **Effects of Vulcanization**:
- The cross-linking of rubber chains through sulfur increases the elasticity and tensile strength of the rubber, making it more durable and useful for various applications.

5. **Conclusion**:
- Therefore, the correct answer to the question is that natural rubber is vulcanized by heating it with sulfur.

### Final Answer:
Natural rubber is vulcanized by heating it with **sulfur**.

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