* Sodium (Na): Sodium has one valence electron in its outermost shell. When it loses this electron, it becomes a positively charged ion called a sodium cation (Na+). Losing an electron leaves it with a full outer shell, making it more stable.

* Chlorine (Cl): Chlorine has seven valence electrons. It wants to gain one more electron to complete its outer shell. When it gains an electron, it becomes a negatively charged ion called a chloride anion (Cl-). Gaining an electron fills its outer shell and makes it more stable.

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 to create sodium chloride (NaCl), or table salt.