Given below are two statement : one is labelled as Assertion `(A) `and the other is labelled as reason `(R).`
Assertion `(A)` : Gypsum is used for making fireproof wall boards.
Reason `(R)` : Gypsum is unstable at high temperatures.
In the light of the above statements, choose the correct answer from the options given below :

Options

A. `(A)` is not correct but `(R)` is correct
B. Both `(A) `and` (R)` are correct and `(R)` is the correct explanation of `(A)`
C. Both `(A)`and `(R)`are correct but `(R)` is not the correct explanation of `(A)`
D. `(A)` is correct but `(R) `is not correct

Answer

To solve the question, we will analyze the Assertion (A) and Reason (R) provided:

### Step 1: Analyze the Assertion (A)
- **Assertion (A)** states: "Gypsum is used for making fireproof wall boards."
- **Explanation**: Gypsum, which is chemically represented as CaSO₄·2H₂O, is indeed used in the construction industry for making fireproof wall boards. This is because gypsum has fire-resistant properties; it can withstand high temperatures and does not easily ignite.

### Step 2: Analyze the Reason (R)
- **Reason (R)** states: "Gypsum is unstable at high temperatures."
- **Explanation**: When gypsum is subjected to high temperatures, it can dehydrate, losing its water molecules (H₂O) and converting into calcium sulfate (CaSO₄). This process indicates that gypsum does not remain stable at high temperatures, which is true.

### Step 3: Determine the Relationship Between Assertion and Reason
- While both statements are correct, the reason does not provide a valid explanation for the assertion. The assertion is about the use of gypsum in fireproofing, while the reason discusses its instability at high temperatures. The fire resistance of gypsum is due to its ability to form a protective layer when heated, rather than its stability.

### Conclusion
- Therefore, the correct answer is that both the assertion and reason are correct, but the reason is not the correct explanation for the assertion.

### Final Answer
- **Option 3**: Both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

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