* Barium (Ba) is a metal in Group 2 of the periodic table. Metals tend to lose electrons to form positively charged ions (cations). Barium readily loses two electrons to form a +2 ion (Ba²⁺).
* Oxygen (O) is a nonmetal in Group 16 of the periodic table. Nonmetals tend to gain electrons to form negatively charged ions (anions). Oxygen gains two electrons to form a -2 ion (O²⁻).
* Ionic Bonding: The electrostatic attraction between the positively charged barium ion (Ba²⁺) and the negatively charged oxide ion (O²⁻) forms the ionic bond in barium oxide.
The chemical formula for barium oxide is BaO, reflecting the 1:1 ratio of barium and oxygen ions needed to achieve electrical neutrality.
