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JEE Main levelSingle correct optionDifficulty 2 of 3g2070

Assertion (A): Pyrrole is a much weaker base than pyridine. Reason (R): The nitrogen lone pair in pyrrole is part of the aromatic pi sextet, whereas in pyridine it lies in an sp orbital in the plane of the ring.

  1. ABoth A and R are true but R is not the correct explanation of A
  2. BA is true but R is false
  3. CBoth A and R are true and R is the correct explanation of A
  4. DA is false but R is true

Answer: C

Both statements are true. Because the pyrrole N lone pair is needed for aromaticity, it is unavailable for protonation, while the pyridine lone pair is orthogonal to the pi system and free to bind . So R explains A.
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