Given that the $\mathrm{N}$ shell of an element contains 10 electrons, write the electronic configuration of the stable ion.

The electronic configuration of Ni.

1. The total number of electrons in the element $=$ the number of electrons in $\mathrm{K}+\mathrm{L}+\mathrm{M}+\mathrm{N}$ shells i.e. $2+8+8+10=28$.
2. So, atomic no. of element is 28 (Nickel).
3. The electronic state of a stable ion $N{i}^{2+}=2,8,8,8$