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Model Paper 3 — Chemistry STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 ScienceChemistryModel Paper 32 Marks
Question
Explain why the system are not aromatic.
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Answer

For the given compound, the number of $\pi$-electrons is 8 .
By Huckel's rule,
$
\begin{aligned}
& \Rightarrow 4 n+2=8 \\
& \Rightarrow 4 n=6 \\
& \Rightarrow n=3 / 2
\end{aligned}
$
This is not true for the given compound as it is a fraction. Hence, it is not aromatic in nature.

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