produce ions
So far we have looked at ionic compounds, in which atoms of various elements gain or lose electrons to produce ions. The resulting ions are held together by strong attractions between oppositely charged particles. However, this only works for bonds between atoms in which one partner the metal has a tendency to lose electrons, and the other the nonmetal has a tendency to gain them. Then how might two nonmetals, such as nitrogen and oxygen, form chemical bonds? Neither is likely to lose electrons and become a cation, but both require more electrons to reach a noble gas configuration. Instead of a complete transfer of electrons, these atoms can bond by sharing electrons, producing what is called a covalent bond . When a group of atoms are joined together by covalent bonds, the resulting structure is called a molecule . Molecules are generally much smaller than the extended three-dimensional networks of ions that are seen in ionic compounds. We will look much more at covalent bonding and molecules in future chapters, but for now, we will focus on the ways in which molecules are named.