What is the difference between Ionic and Molecular compounds

Ionic compounds are between cation and anions. They are usually between a metal and a nonmetal or a polyatomic ion. Ionic compounds are bonded with the cation “giving away” its valence electrons and the anion “receiving” them for a full octet.

Molecular compounds are usually between two or more nonmetals. The nonmetals simply share their valence electrons for a full octet.

When the difference in electronegativity of two atoms is greater than 1.7, the bond is ionic. When it is less than 1.7 but greater than 0.4, the bond is polar covalent. When the difference is less than 0.4, the bond is nonpolar covalent.

One difference between molecular compounds and ionic compounds is that molecular compounds are formed by the sharing of electrons, and ionic compounds are formed by the transfer of electrons. Molecular compounds result from covalent bonding and ionic compounds result from ionic bonding. Another difference is that a molecular bond is formed between two non-metals, and an ionic bond is formed between a metal and a non-metal.