Which of the following is a linear polymer ?

Options

A. Nylon
B. Bakelite
C. Low density polythene
D. Melamine-formaldehyde polymer.

Answer

To determine which of the given options is a linear polymer, we need to first understand what a linear polymer is and then analyze each option provided.

### Step-by-Step Solution:

1. **Define Linear Polymer**:
A linear polymer is a type of polymer where the monomeric units are linked together in a straight, unbranched chain. This structure allows for a more orderly arrangement of the polymer chains.

2. **Identify Examples of Linear Polymers**:
Common examples of linear polymers include:
- High-density polyethylene (HDPE)
- Polyvinyl chloride (PVC)
- Nylon

3. **Examine the Options**:
Let's analyze each option provided in the question:
- **Option 1: Nylon**
- Nylon is a synthetic polymer known for its linear structure, making it a linear polymer.
- **Option 2: Bakelite**
- Bakelite is a type of cross-linked polymer, which means it has a network structure rather than a linear one.
- **Option 3: Low-Density Polyethylene (LDPE)**
- LDPE is a branched-chain polymer, characterized by its short branches off the main chain.
- **Option 4: Melamine-Formaldehyde Polymer**
- This is also a cross-linked polymer, similar to Bakelite, and does not have a linear structure.

4. **Conclusion**:
Based on the analysis, the only linear polymer among the options is **Nylon** (Option 1).

### Final Answer:
The linear polymer from the given options is **Nylon**.

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