Cerium(IV) () solutions are widely and effectively used as standard oxidizing agents in volumetric a — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Cerium ($Z=58$) readily loses four electrons to form $Ce^{4+}$, achieving a highly stable empty-shell (noble gas) configuration ($[Xe] 4f^0$). However, the most universally stable oxidation state for all lanthanides in aqueous media is strictly $+3$. Consequently, $Ce^{4+}$ possesses a strong thermodynamic drive to capture one electron and revert to $Ce^{3+}$, acting as an excellent analytical oxidizing agent.