Here's why:
* Ionic bonds form between a metal and a nonmetal.
* Metals tend to lose electrons, becoming positively charged ions (cations).
* Nonmetals tend to gain electrons, becoming negatively charged ions (anions).
* The strong electrostatic attraction between these oppositely charged ions is what constitutes the ionic bond.
Example: In the formation of sodium chloride (NaCl), sodium (Na) loses an electron to become a positively charged ion (Na+), while chlorine (Cl) gains an electron to become a negatively charged ion (Cl-). The opposite charges attract, forming the ionic bond.
