Vulcanised rubber contains

Options

A. about 3-5% sulphur
B. about 30% sulphur
C. about 5% carbon black
D. about 15-20% carbon black

Answer

**Step-by-Step Solution:**

1. **Understanding Vulcanized Rubber**: Vulcanized rubber is a type of rubber that has undergone a chemical process known as vulcanization. This process enhances the properties of natural rubber, making it more durable and elastic.

2. **Vulcanization Process**: The vulcanization process involves the addition of a vulcanizing agent, which is typically sulfur. This agent helps to create cross-links between the polymer chains in natural rubber.

3. **Composition of Vulcanized Rubber**: Vulcanized rubber generally contains:
- **Sulfur**: The amount of sulfur used in the vulcanization process can vary, but it typically ranges from 3% to 5% for standard applications. In some formulations, it can go as high as 30% or even more, depending on the desired properties of the rubber.
- **Carbon Black**: This is often added to improve the strength, durability, and wear resistance of the rubber. It also helps in reinforcing the rubber.

4. **Final Composition**: Therefore, vulcanized rubber contains a combination of sulfur (in varying percentages) and carbon black, along with the original rubber polymer.

**Final Answer**: Vulcanized rubber contains 3-5% sulfur and carbon black.

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