What are ionic bonds primarily formed between?

Ionic bonds are primarily formed between atoms that have a large difference in electronegativity. In this context, electronegativity refers to the tendency of an atom to attract electrons in a chemical bond. When two atoms have significantly different electronegativities, one atom, typically a metal, will lose electrons, while another atom, usually a nonmetal, will gain electrons. This transfer of electrons results in the formation of positively charged cations and negatively charged anions, which are held together by the electrostatic forces of attraction in an ionic bond.

The large electronegativity difference is critical because it ensures that one atom can effectively pull electrons away from another, leading to the strong ionic interactions that characterize ionic compounds. Understanding this concept is essential for grasping the fundamental nature of ionic bonding, which is a key aspect of chemical bonding in physical science.