MCQ
Which one of the lanthanoids given below is the most stable in divalent form?
  • A
    $Ce$ (Atomic Number $58$)
  • B
    $Sm$ (Atomic Number $62$)
  • $Eu$ (Atomic Number $63$)
  • D
    $Yb$ (Atomic Number $70$)

Answer

Correct option: C.
$Eu$ (Atomic Number $63$)
c
$E _{ M ^{3+} / M ^{2+}}^{0} \Rightarrow Eu(-0.35) Yb(-1.05$

Hence, due to more reduction potential in $Eu$ as compared to $Yb$, it can concluded that $Eu ^{2+}$ is more stable than $Yb ^{2+}$.

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