Question 11
What are the necessary conditions for any system to be aromatic?
A compound is said to be aromatic if it satisfies the following three conditions:
(i) It should be cyclic ,so that each p orbital should overlap with adjacent p orbital to become aromatic

(ii) It should be planar i.e, All adjacent p orbitals must be aligned so that the p electron density can be delocalized.

(iii) It should be completely conjugated i.e, Aromatic compounds must have a p orbital on every atom and each must overlap with adjacent p orbitals.

(iv) The total number of π–electrons present in the ring should be equal to (4n + 2), where n = 0, 1, 2 … etc. This is known as Huckel’s rule.