* Sodium (Na): Sodium has an atomic number of 11, meaning it has 11 electrons. Its electron configuration is 1s² 2s² 2p⁶ 3s¹. When sodium loses one electron, it becomes a positively charged ion (Na⁺) with the electron configuration 1s² 2s² 2p⁶, which is the same as the noble gas neon (Ne).
* Fluorine (F): Fluorine has an atomic number of 9, meaning it has 9 electrons. Its electron configuration is 1s² 2s² 2p⁵. When fluorine gains one electron, it becomes a negatively charged ion (F⁻) with the electron configuration 1s² 2s² 2p⁶, which is also the same as the noble gas neon (Ne).
In summary:
By losing an electron, sodium achieves a stable electron configuration like neon. By gaining an electron, fluorine also achieves a stable electron configuration like neon. This tendency to gain or lose electrons to achieve a stable noble gas configuration is a key principle in ionic bonding.
