1. NaCl - Ionic formed by the transfer of electrons between a metal, sodium, and a non-metal, chlorine 2. H2O - Covalent formed by the sharing of electrons between two non-metals, hydrogen and oxygen 3. Cu - Metallic copper is a metal and its bonding is characterized by a sea of delocalized electrons 4. Fe2O3 - Ionic formed by the transfer of electrons between a metal, iron, and a non-metal, oxygen 5. CO2 - Covalent formed by the sharing of electrons between two non-metals, carbon and oxygen