Assertion (A) Network polymers are thermosetting
Reason (R ) Network Polymers have high molecular mass

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

To solve the assertion and reason question regarding network polymers and their characteristics, we can break down the solution into clear steps:

### Step 1: Understand the Assertion
The assertion states that "Network polymers are thermosetting."
- **Explanation**: Thermosetting polymers are a type of polymer that, once set into a given shape, cannot be remolded or reheated to change their shape. They undergo a process called cross-linking during polymerization, which creates a rigid structure.

### Step 2: Understand the Reason
The reason states that "Network polymers have high molecular mass."
- **Explanation**: Network polymers are formed through extensive cross-linking, leading to a three-dimensional structure. This structure contributes to their high molecular mass, as they consist of many repeating units that are interconnected.

### Step 3: Evaluate the Assertion and Reason
- **Assertion Evaluation**: The assertion is correct; network polymers are indeed thermosetting due to their cross-linked structure.
- **Reason Evaluation**: The reason is also correct; network polymers do have high molecular mass because of their 3D structure. However, the reason does not directly explain why network polymers are thermosetting. The key characteristic of thermosetting polymers is the cross-linking, which is not explicitly mentioned in the reason.

### Step 4: Conclusion
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Therefore, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

### Final Answer
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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