Question

Give two examples of cations having completely filled K and L shells.

Answer 1

• ${\mathrm{Na}}^{+1}$,sodium has 11 electrons .sodium atom loses one electron and forms uni positive cation.
• Now it has only 10 electrons. It has an electronic configuration: 2,8 where both K and L shells are completely filled.
• ${\mathrm{K}}^{+1}$, potassium has 19 electrons. When it loses one electron and forms a uni positive cation, the number of electrons is reduced to 18. Hence the electronic configuration is 2,8,8. It has a completely filled K,L, and M shells.