Writing + Naming Ionic and Covalent Compounds

Ionic Compounds-Composed of 2 or more particles(oppsitely charged), which is Metal and NON- Metal
Ex.
K+1  ,   N3-   >   K3N , as three more Potassium get 3 positive charge to held with Nitrogen 3- and get the balance- 0.

Copper (I) Oxide > Cu2O 
Copper has two different charge as we see in the periodic table, that's why we have to notice that which charge do we use it.   If it's +2, we use Roman number notice it by (II).

Covalent Compound
-Share electrons
-Compose with NON- Metal and NON- Metal

Diatomic molecules: H2, O2, F2, Br2, N2, Cl2, I2
-Use GREEK prefixes to Indicade the number of atoms.

mono-1  di-2  tri-3  tetra-4 penta-5 hexa-6 hepta-7 octa-8 nona-9 deca-10

Ex.
N2O4 >  dinitrogen tetroxide