1. Naming Covalent/ Molecular Compounds

2. Covalent Bonds use Prefixes to indicate the number of atoms involved in the compounds 1= mono6 = hexa 2 = di7= hepta 3 = tri8 = octa 4 = tetra9 = nina 5 = penta10 = deca

3. RULES 1- The name of the first element does not get changed, only a prefix is added if it is more than one. Ex: Trisulfur tetrafluoride S 3 F 4 2- The second element gets a different ending, as well as a prefix. Ex : phosphorus trichloride PCl 3 (NOT: phosphorus trichlorine)

4. RULES continued.. 3- If the first element in the compound is a single you do not write mono: ex. CO 2 - carbon dioxide (NOT monocarbon dioxide) 4- If the element’s name starts with a vowel, and the prefix ends with a vowel, you can drop the last vowel on the prefix: ex. S 5 O 10 - pentasulfur decoxide (NOT pentasulfur decaoxide)

5. RULES continued.. 5- Covalent compounds do not get simplified. Name the compound exactly as you see it: Ex. H 2 F 2 = dihydrogen difluoride (NOT hydrogen monofluoride HF)

6. TRY THESE: a)Diphosphorus pentoxide b)Nitrogen monoxide c)Xenon hexafluoride d)Tetrarsenic decoxide e) SiO 2 f) N 2 S 5 g)P 4 O 10 h)BrCl 6