Question

Choose the stable oxidation states of cerium ( $Ce$ ).

• A. $+1$ and $+2$
• B. $+3 \, $ and $+4$
• C. $+2 \, $ and $+3$
• D. $+2$ and $+7$

Answer 1

Answer: (B)

Cerium is one of the lanthanides. Electronic configuration of cerium is given below.

$\_{58}^{}Ce \rightarrow \left[Xe\right] \, 4f^{1} \, 5d^{1} \, 6s^{2}$

As per the electronic configuration of cerium, it has the ability to show $+2$ and $+4$ oxidation states.

$\text{Ce}^{\text{3+}} \rightarrow \left[\text{Xe}\right] \text{ 4f}^{\text{1}} \text{ 5d}^{\text{0}} \text{ 6s}^{\text{0}}$ (common in all Lanthenoids)

$Ce^{4 +} \rightarrow \left[Xe\right] \, 4f^{0} \, 5d^{0} \, 6s^{0}$