Question

The most common oxidation state of Lanthanoids is:

• A. 4
• B. 3
• C. 6
• D. 2

Answer 1

Answer: (B)

3

Lanthanoids with general electronic configuration $\left[Xe\right]4f^{1-14}5d^{0-1}6s^2$ have +3 as the most common oxidation state. It is obtained by loss of $2$ electrons. $6s$ electrons and one $5d$ or $4f$ electron.