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Assertion : Cyclopentadienyl anion is much more stable than allyl anion.Reason : Cyclopentadienyl anion is aromatic in character.

  1. A
    (a)
  2. B
    (b)
  3. C
    (c)
  4. D
    (d)

Solution & Step-by-step Explanation

The cyclopentadienyl anion is exceptionally stable because it satisfies Huckel's rule for aromaticity: it is a planar, cyclic system with electrons ( in ). In contrast, the allyl anion is stabilized only by resonance and is not aromatic. Aromatic stabilization is significantly stronger than simple resonance stabilization. Both assertion and reason are true and the reason provides the correct explanation.
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Assertion : Cyclopentadienyl anion is much more stable than allyl anion.Reason : Cyclopentadienyl anion is aromatic in character.
A
(a)
B
(b)
C
(c)
D
(d)

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Organic ChemistryResonanceAromaticity

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