* 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+). This is because it now has one fewer electron than protons.

* Chlorine (Cl): Chlorine has seven valence electrons in its outermost shell. It wants to gain one more electron to complete its outer shell. When it gains an electron from sodium, it becomes a negatively charged ion called a chloride anion (Cl-). This is because it now has one more electron than protons.

In summary:

* Sodium atom (Na) -> Sodium cation (Na+)

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

This process is called ionic bonding where the oppositely charged ions attract each other and form a strong electrostatic bond.