* Calcium (Ca) is a metal in Group 2 of the periodic table. Metals tend to lose electrons to achieve a stable electron configuration. Calcium loses two electrons to become a positively charged ion, Ca²⁺.
* Bromine (Br) is a nonmetal in Group 17 of the periodic table. Nonmetals tend to gain electrons to achieve a stable electron configuration. Bromine gains one electron to become a negatively charged ion, Br⁻.
The electrostatic attraction between the positively charged calcium ion (Ca²⁺) and the negatively charged bromide ions (Br⁻) forms the ionic bond in calcium bromide (CaBr₂).
