$Mn^{2+}$ compounds are more stable than $Fe^{2+}$ compounds towards oxidation to their $+3$ state,because

The atomic number of $Pd$ is $46$. The atomic numbers of the elements lying immediately above and below it in the same group are,respectively,.....................

The correct decreasing order of spin only magnetic moment values $(BM)$ of $Cu^{+}$,$Cu^{2+}$,$Cr^{2+}$ and $Cr^{3+}$ ions is $:$

Transition elements show high melting points. Why?

Observe the following statements:
$a$) The basic strength of $Lu(OH)_3$,$Gd(OH)_3$ and $Ce(OH)_3$ follows the order: $Ce(OH)_3 > Gd(OH)_3 > Lu(OH)_3$
$b$) $O^{2-}$,$N^{3-}$,$F^{-}$ and $Na^{+}$ are isoelectronic species
$c$) The sizes of $Zr$ and $Hf$ are approximately the same
The correct statements are:

Out of all the known elements, the percentage of transition elements (including inner transition elements) is approximately $......\%$