The predominant oxidation state universally displayed by the lanthanide series of elements is_________?
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Answer: A. +3
Explanation
Lanthanides characteristically exhibit a stable plus three oxidation state in compounds. Removing three electrons achieves a stable electronic structure resembling noble gases. This uniform oxidation state dominates the chemical behavior of the entire rare earth series. The lanthanide series comprises fifteen metallic elements spanning atomic numbers fifty-seven. Inner f-orbitals are shielded effectively by outer shell electrons in these heavy atoms. Oxidation states describe the apparent charge of atoms within chemical bonds and compounds.
Lanthanides are critical components in modern electronics, magnets, and green energy technologies. Similar chemical properties make separating individual lanthanide elements a difficult challenge. Rare earth phosphors rely on lanthanide oxidation states for glowing screen displays. Plus two is an alternative oxidation state observed in only a few specific lanthanides. Plus one is generally unstable and not observed for the lanthanide series of elements. Plus four occurs in cerium and terbium but is not the predominant state universally.
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