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In the following questions, a statement ...

In the following questions, a statement of assertion (A) is following by a statement of reason (R )
A : Halogen is deactivating group due to -I effect.
R: Halogen is ortho -para directing due to +M effect .

A

If both Assertion & Reason are the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark(2).

C

If Assertion is true statement but Reason is false , then mark (3)

D

If both Assertion and Reason are false statements, then mark (4)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion (A) and the reason (R) provided. **Assertion (A):** Halogen is a deactivating group due to -I effect. **Reason (R):** Halogen is ortho-para directing due to +M effect. ### Step-by-Step Solution: 1. **Understanding the Assertion (A):** - Halogens (F, Cl, Br, I) are highly electronegative elements. - Due to their electronegativity, they attract the shared pair of electrons towards themselves when attached to a benzene ring. - This results in a decrease in electron density on the benzene ring, making it less reactive towards electrophilic substitution reactions. - Therefore, halogens act as deactivating groups due to the -I (inductive) effect. **Conclusion:** The assertion is **true**. 2. **Understanding the Reason (R):** - Halogens possess lone pairs of electrons that can participate in resonance. - When a halogen is attached to a benzene ring, it can donate its lone pair to the ring, increasing the electron density at the ortho and para positions. - This results in the benzene ring being more reactive towards electrophiles at these positions, making halogens ortho-para directing groups due to the +M (mesomeric) effect. **Conclusion:** The reason is also **true**. 3. **Evaluating the Relationship Between A and R:** - While both statements are true, the reason does not explain the assertion. - The assertion states that halogens are deactivating due to the -I effect, while the reason discusses the +M effect, which is related to their directing influence rather than their deactivating nature. ### Final Conclusion: - Since both the assertion and the reason are true, but the reason does not correctly explain the assertion, the correct option is: **Option 2:** Both assertion and reason are true, but the reason is not the correct explanation of the assertion. ---
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