* Sodium (Na) has one electron in its outermost shell. It wants to lose this electron to achieve a stable, filled outer shell like the noble gases.

* Chlorine (Cl) has seven electrons in its outermost shell. It wants to gain one electron to achieve a stable, filled outer shell.

The Transfer:

Sodium easily loses its one electron to become a positively charged ion (Na+). Chlorine readily gains that electron to become a negatively charged ion (Cl-). The opposite charges attract each other strongly, forming an ionic bond.

Key Points:

* Ionic bonds involve the complete transfer of electrons from one atom to another, creating oppositely charged ions that are attracted to each other.

* Sharing bonds (covalent bonds) involve atoms sharing electrons to achieve stable outer shells.

Let me know if you'd like more details on ionic or covalent bonds!