Assertion : Strong interparticle forces exist in thermosetting polymers.
Reason : Thermosetting polymers are heavily cross linked.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion .
B. If both assertion and reason are true but reason is not the correct explanation of assertion .
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
The assertion states that "Strong interparticle forces exist in thermosetting polymers." This means that the forces holding the polymer chains together in thermosetting polymers are strong.

2. **Understanding the Reason:**
The reason provided is that "Thermosetting polymers are heavily cross-linked." Cross-linking refers to the bonding between different polymer chains, which creates a network structure.

3. **Analyzing the Relationship:**
The strong interparticle forces in thermosetting polymers can be attributed to the extensive cross-linking. When polymers are cross-linked, they form a three-dimensional network that enhances the strength and stability of the material.

4. **Examples of Thermosetting Polymers:**
A common example of a thermosetting polymer is Bakelite. In Bakelite, the polymer chains are interconnected through cross-links, which makes the material rigid and heat-resistant.

5. **Conclusion:**
Since both the assertion and the reason are true, and the reason correctly explains why the assertion is true, we conclude that both the assertion and reason are valid.

**Final Answer:**
Both assertion and reason are true, and the reason is the correct explanation for the assertion.

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