What are ionic compounds? Explain their formation with a suitable example.

Ionic compounds are chemical compounds formed by the electrostatic attraction between oppositely charged ions. They are typically formed between a metal and a non-metal, where the metal atom loses electrons to form a positive ion (cation) and the non-metal atom gains electrons to form a negative ion (anion). For example, in the formation of sodium chloride (NaCl), sodium (Na) loses one electron to become Na+, and chlorine (Cl) gains one electron to become Cl-. The electrostatic attraction between Na+ and Cl- forms the ionic bond.