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Assertion: In case of aryl halides, halo...

Assertion: In case of aryl halides, halogens are moderately deactivating.
Reason: Halogens are ortho, para directing groups.

A

If both assertion and reson 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.

Text Solution

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The correct Answer is:
To solve the assertion and reason question regarding aryl halides, we will analyze both the assertion and the reason step by step. ### Step 1: Analyze the Assertion **Assertion:** In case of aryl halides, halogens are moderately deactivating. - Aryl halides are compounds where a halogen atom is bonded to an aromatic ring (like benzene). - Halogens (F, Cl, Br, I) are more electronegative than carbon. This means they attract electrons towards themselves. - When a halogen is attached to the benzene ring, it pulls electron density away from the ring due to its electronegativity. - As a result, the carbon atoms in the benzene ring become electron deficient, leading to a decrease in the reactivity of the ring towards electrophilic substitution reactions. - Therefore, the assertion is **true**: halogens do deactivate the aryl ring moderately. ### Step 2: Analyze the Reason **Reason:** Halogens are ortho, para directing groups. - Halogens can donate some of their lone pair electrons to the aromatic ring through resonance, which increases the electron density at the ortho and para positions relative to the halogen. - This means that when a substitution occurs, the incoming electrophile is more likely to attack the ortho or para positions rather than the meta position. - Thus, the reason is also **true**: halogens are indeed ortho, para directing groups. ### Step 3: Determine the Relationship Between Assertion and Reason - While both the assertion and the reason are true, the reason does not explain why halogens deactivate the aryl ring. - The assertion is based on the electronegativity of halogens and their ability to withdraw electron density from the ring, while the reason focuses on the directing effects of halogens in electrophilic substitution reactions. - Therefore, the reason is not the correct explanation for the assertion. ### Conclusion Both the assertion and the reason are true, but the reason is not the correct explanation for the assertion. ### Final Answer The correct option is: Both assertion and reason are true, but reason is not the correct explanation of assertion. ---
To solve the assertion and reason question regarding aryl halides, we will analyze both the assertion and the reason step by step. ### Step 1: Analyze the Assertion **Assertion:** In case of aryl halides, halogens are moderately deactivating. - Aryl halides are compounds where a halogen atom is bonded to an aromatic ring (like benzene). - Halogens (F, Cl, Br, I) are more electronegative than carbon. This means they attract electrons towards themselves. - When a halogen is attached to the benzene ring, it pulls electron density away from the ring due to its electronegativity. ...
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