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Assertion (A) Elementary phosphorus exis...

Assertion (A) Elementary phosphorus exists in three principal
allotropic forms , ie .white (or yellow),red (or violet ) and black.
Reason (R ) Of the three forms, white phosphorus is the most important and most reactive.

A

If both Assertion and Reason are true and Reason is 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 and false.

Text Solution

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The correct Answer is:
To solve the given question, we need to analyze the Assertion (A) and Reason (R) statements regarding the allotropes of phosphorus. ### Step-by-Step Solution: 1. **Understanding Assertion (A)**: - The assertion states that elementary phosphorus exists in three principal allotropic forms: white (or yellow), red (or violet), and black. - This statement is **correct**. Phosphorus does indeed exist in these three main allotropes. 2. **Understanding Reason (R)**: - The reason states that of the three forms, white phosphorus is the most important and most reactive. - This statement is also **correct**. White phosphorus is known for its high reactivity compared to red and black phosphorus. 3. **Analyzing the Relationship**: - While both statements are correct, we need to determine if the reason correctly explains the assertion. - White phosphorus is indeed the most reactive form, and it is the precursor from which red and black phosphorus are derived. However, the assertion does not depend on the reason being true; it simply states a fact about the existence of the allotropes. 4. **Conclusion**: - Both Assertion (A) and Reason (R) are true, but the reason does not provide a correct explanation for the assertion. Therefore, the final answer is that both statements are true, but the reason is not the correct explanation for the assertion. ### Final Answer: - Assertion (A) is true. - Reason (R) is true, but it is not the correct explanation for Assertion (A). ---
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