The Actinoid elements possess highly comparable orbital energies, allowing them to utilize an immens — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Unlike Lanthanides which rarely stray far from $+3$, the earlier Actinides (from Actinium up to Americium) show an incredibly wide range of oxidation states. Because the $5f, 6d$, and $7s$ energy levels are nearly indistinguishable, all these valence electrons can participate in chemical bonding. Both Neptunium ($Np$) and Plutonium ($Pu$) are well documented to reach an absolute maximum oxidation state of exactly $+7$.