Naming Covalent Naming Covalent CompoundsCompounds

Binary Covalent CompoundsBinary Covalent Compounds

Two Systems of Two Systems of NamingNaming Traditional SystemTraditional System

– Place least electronegative element firstPlace least electronegative element first– Higher electronegative element second Higher electronegative element second

and has “ide” endingand has “ide” ending– Use prefixes to give number of atomsUse prefixes to give number of atoms

ExceptionsExceptions– HH22O (not O (not dihydrogen monoxidedihydrogen monoxide))

– OO22 (not (not dioxygendioxygen))

– NHNH33 (not (not nitrogen trihydridenitrogen trihydride))

Prefixes forPrefixes forTraditional SystemTraditional System

# of # of AtomsAtoms

PrefixPrefix # of # of AtomsAtoms

PrefixPrefix

11 MonoMono 66 HexaHexa

22 DiDi 77 HeptaHepta

33 TriTri 88 OctaOcta

44 TetraTetra 99 NonaNona

55 PentaPenta 1010 DecaDeca

StemsStems

H = H = hydrhydr

C = C = carbcarb

N = nitrN = nitr O = oxO = ox F = F = fluorfluor

Si = Si = silicsilic

P = P = phosphphosph

S = sulfS = sulf Cl = Cl = chlorchlor

As = As = arsenarsen

Se = Se = selenselen

Br = Br = brombrom

Te = Te = tellurtellur

I = iodI = iod

Traditional NamingTraditional Naming

ClCl22OO33

SOSO22

NN22HH44

NONO

NONO22

NN22OO

Dichlorine trioxideDichlorine trioxide

Sulfur dioxideSulfur dioxide

Dinitrogen tetrahydrideDinitrogen tetrahydride

Nitrogen monoxideNitrogen monoxide

Nitrogen dioxideNitrogen dioxide

Dinitrogen monoxideDinitrogen monoxide

Two Systems of Two Systems of NamingNaming Stock SystemStock System

– Place least electronegative element firstPlace least electronegative element first– Determine its oxidation stateDetermine its oxidation state ( (apparent apparent

chargecharge)) Rules: FRules: F-1 -1 (Halides)(Halides) , O, O-2-2

– Use Use Roman NumeralsRoman Numerals to indicate this to indicate this oxidation number oxidation number

– Higher electronegative element second Higher electronegative element second and has the “ide” endingand has the “ide” ending

Stock System NamesStock System Names

COCO NONO NONO22

NONO33

NN22OO55

PClPCl33 SiHSiH44

Carbon (II) oxideCarbon (II) oxide

Nitrogen (II) oxideNitrogen (II) oxide

Nitrogen (IV) oxideNitrogen (IV) oxideNitrogen (VI) oxideNitrogen (VI) oxide

Nitrogen (V) oxideNitrogen (V) oxidePhosphorus (III) chloridePhosphorus (III) chlorideSilicon (IV) hydrideSilicon (IV) hydride