Those elements whose two outermost orbitals are incompletely filled with electrons are known as:

Which of the following compounds is colored?

Which of the following pairs of substances exhibit paramagnetism among $K_2SO_4$,$MgCl_2$,$FeSO_4$,$NiCl_2$,and $ZnO$?

Which of the following ions is paramagnetic?

Determine whether the following statements are True $(T)$ or False $(F)$:
$(a)$ The atomic radii of the elements of the second transition series $(4d)$ are larger than those of the first transition series $(3d)$.
$(b)$ $Cr^{+}$,$Mn^{2+}$,and $Fe^{3+}$ have the same electronic configuration.
$(c)$ $Cr^{+}$,$Mn^{2+}$,and $Fe^{3+}$ have the same $d^5$ electronic configuration.

In the $3d$ series of transition elements,the atomic radius of $Zn$ increases instead of decreasing because...