Question

Lanthanide for which $+II$ and $+III$ oxidation states are common, is

• A. $La$
• B. $Nd$
• C. $Ce$
• D. $Eu$

Answer 1

Answer: (D)

Outer electronic configuration of Eu (Z = 63) is $4f^{7}6s^2$ . As the outer electronic configuration of $E{u}^{2+}$ is $4f^2$ , making it stable and all lanthanides show $+3$ oxidation state. Thus, Eu exhibits $+2$ and $+3$ oxidation states.