The transition element that has the lowest enthalpy of atomisation is

$d-d$ transition occurs in . . . . . . .

For the ions $Zn^{2+}, Ni^{2+}$ and $Cr^{3+}$ which among the following statements is correct?
(Atomic number of $Zn = 30, Ni = 28$ and $Cr = 24$)

Name the periodic element,which does not show variable oxidation states.

Transition elements form complex compounds primarily due to:

Among $Sc$,$Mn$,$Co$ and $Cu$,identify the element with the highest enthalpy of atomisation. The spin-only magnetic moment value of that element in its $+2$ oxidation state is $......... \text{BM}$ (in nearest integer).