MCQ
The pair of lanthanides in which both elements have high third-ionization energy is:
- A$Eu , Gd$
- ✓$Eu , Yb$
- C$Lu , Yb$
- D$Dy, Gd$
$\left.Yb ^{+2}:[ Xe ] 4 f ^{14}\right\}$ filled \& fully filled configurations
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$\begin{array}{*{20}{c}} {C{H_2}OH} \\ {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ {C{H_2}OH} \end{array}$ $+$ oxalic acid $\xrightarrow{{{{210}^o}C}}$ $\quad\quad X$
$\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad$(major product)
