7-bromo-1,3,5-cycloheptatriene exists as ionic species in aqueous solution while 5-bromo-1,3-cyclopentadiene doesn't ionise even in presence of `Ag^(+)(aq)`, Explain.

Explanation

The C-Br bond in the case of 7-bromo-1,3,5-cycloheptatriene is broken easily because the intermediate carbocation formed is very stable [aromatic as it contains `(4n+2)pie^(-)` i.e., follows huckle rule] while it does not break easily in the case of 5-bromo-1,3 cyclopenta diene because carbocation formed here is highly unstable as it is anti aromatic i.e., does not follows huckel rule. (it contains `4pi` electrons).