* Electronegativity Difference: The electronegativity difference between calcium (1.0) and chlorine (3.16) is 2.16. This is a large difference, indicating that chlorine has a much stronger attraction for electrons than calcium.
* Electron Transfer: The large electronegativity difference leads to the transfer of electrons from calcium to chlorine. Calcium loses two electrons to achieve a stable noble gas configuration, becoming a Ca²⁺ cation. Chlorine gains one electron each to achieve a stable noble gas configuration, becoming two Cl⁻ anions.
* Electrostatic Attraction: The oppositely charged ions (Ca²⁺ and Cl⁻) are held together by strong electrostatic forces, forming an ionic bond.
Key takeaway: Large electronegativity differences between atoms lead to the formation of ionic bonds.
