1. Naming Covalent Compounds Binary Covalent Compounds

2. Two Systems of Naming Traditional System Traditional System –Place least electronegative element first –Higher electronegative element second and has “ide” ending –Use prefixes to give number of atoms Exceptions Exceptions –H 2 O (not dihydrogen monoxide) –O 2 (not dioxygen) –NH 3 (not nitrogen trihydride)

3. Prefixes for Traditional System # of Atoms Prefix Prefix 1Mono6Hexa 2Di7Hepta 3Tri8Octa 4Tetra9Nona 5Penta10Deca

4. Stems H = hydr C = carb N = nitr O = ox F = fluor Si = silic P = phosph S = sulf Cl = chlor As = arsen Se = selen Br = brom Te = tellur I = iod

5. Traditional Naming Cl 2 O 3 SO 2 N2H4N2H4N2H4N2H4 NO NO 2 N2ON2ON2ON2O Dichlorine trioxide Sulfur dioxide Dinitrogen tetrahydride Nitrogen monoxide Nitrogen dioxide Dinitrogen monoxide

6. Two Systems of Naming Stock System Stock System –Place least electronegative element first –Determine its oxidation state (apparent charge) Rules: F -1 (Halides), O -2 Rules: F -1 (Halides), O -2 –Use Roman Numerals to indicate this oxidation number –Higher electronegative element second and has the “ide” ending

7. Stock System Names CO CO NO NO NO 2 NO 2 NO 3 NO 3 N 2 O 5 N 2 O 5 PCl 3 PCl 3 SiH 4 SiH 4 Carbon (II) oxide Nitrogen (II) oxide Nitrogen (IV) oxide Nitrogen (VI) oxide Nitrogen (V) oxide Phosphorus (III) chloride Silicon (IV) hydride