Which specific electrophilic aromatic substitution reaction exhibits a measurable kinetic isotope ef — Aromatic Hydrocarbons Chemistry Question

💡 Solution & Explanation

Sulfonation is highly reversible. The intermediate can either revert to reactants or lose a proton. Because these two paths have similar activation energies, making the C-H bond harder to break (by using C-D) slows the forward path, resulting in a measurable isotope effect.