* Sodium (Na): Sodium has one valence electron in its outermost shell. It wants to lose this electron to achieve a stable electron configuration like the noble gas neon (Ne). When it loses this electron, it becomes a positively charged ion called a sodium cation (Na+).

* Chlorine (Cl): Chlorine has seven valence electrons. It wants to gain one electron to achieve a stable electron configuration like the noble gas argon (Ar). When it gains an electron, it becomes a negatively charged ion called a chloride anion (Cl-).

In summary:

* Sodium atom (Na) → Sodium cation (Na+)

* Chlorine atom (Cl) → Chloride anion (Cl-)

This transfer of electrons is the basis of the ionic bond that forms between sodium and chlorine, resulting in the compound sodium chloride (NaCl), or table salt.