In the potential energy profile of a standard two-step electrophilic aromatic substitution, the aren — Aromatic Hydrocarbons Chemistry Question

💡 Solution & Explanation

The arenium ion (sigma complex) is a true reaction intermediate, not a transition state. Therefore, it resides in a local potential energy minimum (a "valley") bounded by the higher-energy transition state for its formation and the lower-energy transition state for proton loss.