MCQ
An aromatic compounds among other things should have a $\pi $- electron cloud containing electrons where $n$ can't be
  • $0.5$
  • B
    $3$
  • C
    $2$
  • D
    $1$

Answer

Correct option: A.
$0.5$
a
(a) According to Huckel ruel, all aromatic compounds must have $(4n + 2)\pi $ electrons where $n$ is an integer, i.e., $n = 0,\,1,\,2,\,3,\,...$ and possesses unusual stability due to the complete delocalisation of $\pi $- electrons.

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