* Calcium (Ca) is a metal in group 2 of the periodic table, meaning it has 2 valence electrons. It tends to lose these electrons to achieve a stable electron configuration.
* Chlorine (Cl) is a nonmetal in group 17 of the periodic table, meaning it has 7 valence electrons. It tends to gain one electron to achieve a stable electron configuration.
Formation of the Bond:
1. Calcium loses its two valence electrons to become a positively charged calcium ion (Ca²⁺).
2. Two chlorine atoms each gain one electron to become negatively charged chloride ions (Cl⁻).
3. The opposite charges of the calcium and chloride ions attract each other, forming an ionic bond.
The resulting formula is CaCl₂ because two chloride ions are needed to balance the +2 charge of the calcium ion.
