Question

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

Answer 1

• Fluoride ion (${\mathrm{F}}^{-1}$) and chloride ion (${\mathrm{Cl}}^{-1}$) have completely filled K and L shells.
• F has 9 electrons and through the gain of one extra electron, the number of electrons is increased to 10. The new electronic configuration s: 2,8.
• Cl has 17 electrons and through gaining one extra electron the number of electrons is increased to 18. The new electronic configuration is 2,8,8.
• both have filled K and L shells.