CBSE Class 12 · 2000 · All India · d and f Block ElementsVery Short Answer

Which is the most stable oxidation state among the lanthanoids?

Answer: +3 (Ln³⁺).

Solution

The characteristic and most stable oxidation state of all the lanthanoids is +3 (Ln

^{3 +}

); states +2 and +4 occur only for a few elements where they produce extra-stable f

^{0}

, f

^{7}

or f

^{14}

configurations (Ce

^{4 +}

, Eu

^{2 +}

...).

CBSE Class 12 Board · 2000 · All India · Subjective