Which of the following is a thermosetting plastic ?

Options

A. Polyethylene
B. Nylon
C. Terelyne
D. Bakelite

Explanation

To determine which of the following is a thermosetting plastic, we need to understand what thermosetting plastics are and then analyze the options provided.

### Step-by-Step Solution:

1. **Understanding Thermosetting Plastics**:
- Thermosetting plastics are a type of polymer that, once set into a given shape, cannot be remolded or softened by heating. This is due to the formation of cross-linked structures that make them rigid and heat-resistant.

2. **Reviewing the Options**:
- The options given are:
- Polythene
- Nylon
- Pteriline
- Bakelite

3. **Identifying Each Option**:
- **Polythene**: This is a thermoplastic, which means it can be melted and reshaped.
- **Nylon**: This is also a thermoplastic, commonly used in textiles and can be remolded upon heating.
- **Pteriline**: This is a type of synthetic fiber and is not typically classified as a thermosetting plastic.
- **Bakelite**: This is a well-known thermosetting plastic. It is made from phenol and formaldehyde and forms a rigid structure that cannot be melted down again after it has set.

4. **Conclusion**:
- Based on the definitions and characteristics of the materials, Bakelite is the only thermosetting plastic among the options provided.

### Final Answer:
The thermosetting plastic from the options given is **Bakelite**.

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