Ionic Compounds: Naming

Naming Binary Ionic Compounds

1. Always name metal (the cation/+ ion) first

2. Write stemstem of nonmetal (the anion/ - ion)

3. Add ending “ide” to nonmetal

Stems of nonmetals

Iod

Brom

Chlor

Fluor

Hydr is the stem for H

Tellur

SelenArsen

SulfPhosph

OxNitr

The First Step in NamingThe First Step in Naming

• Find metal on PT

• If metal has only one oxidation state it’s easy

• If metal has more than one oxidation state, there’s an extra step

Metals with one oxidation state

• CaO• BaS• AlN• LiCl• Al2Se3

• Na2O• K3N• MgF2

Calcium OxCalcium Oxideide

Barium SulfBarium Sulfideide

Aluminum NitrAluminum Nitrideide

Lithium ChlorLithium Chlorideide

Aluminum SelenAluminum Selenideide

Sodium OxSodium OxideidePotassium NitrPotassium Nitrideide

Magnesium FluorMagnesium Fluorideide

Metals with > 1 oxidation state

• Use formula to figure out which Use formula to figure out which oxidation state metal ion hasoxidation state metal ion has

• Ex: Fe can be Fe+2 oror Fe+3

• Name FeO and Fe2O3

– two differenttwo different compounds – cannot name both iron oxide – every formula has 1 name only

FeO and Fe2O3

• Compounds are electrically neutral

• Oxygen is -2

FeOFeO

Name: Name: Iron (II) oxideIron (II) oxide(roman numeral II = charge on Fe)(roman numeral II = charge on Fe)

1 O which is -21 O which is -2

so Fe must be +2so Fe must be +2

FeO and Fe2O3

• Compounds are electrically neutral

• Oxygen is -2

FeFe22OO33

Each O is -2Each O is -2

There are 3 O’sThere are 3 O’s3 X (-2) = -63 X (-2) = -6Total negative chargeTotal negative charge

Total positive Total positive charge must be +6charge must be +6

Each Fe is +3Each Fe is +3Iron (III) oxideIron (III) oxide

Name the following

• TiCl3• Mn2O4

• Co2O3

• PdBr2

• AuCl3• MoN• MnO• TiO

Titanium (III) chlorideTitanium (III) chloride

Manganese (IV) oxideManganese (IV) oxide

Cobalt (III) oxideCobalt (III) oxide

Palladium (II) bromidePalladium (II) bromide

Gold (III) chlorideGold (III) chloride

Molybdenum (III) nitrideMolybdenum (III) nitride

Manganese (II) oxideManganese (II) oxide

Titanium (II) oxideTitanium (II) oxide

POLYATOMIC IONSPOLYATOMIC IONS

• group of covalently bonded atoms that have a charge

• Table E: (+)’ve or (–)’ve

• polyatomic ions have “names”

• (-) polyatomic ions can form ionic bonds with (+) metal ions

SOSO442-2- CO CO33

2-2- PO PO443-3- OH OH--

Ternary Compounds

• contain 3 or more elements • usually contain a polyatomic ion

– if polyatomic is (+) it’s bonded to a nonmetal– if polyatomic is (–) it’s bonded to a metal– sometimes 2 polyatomics are bonded

together

Formulas with polyatomicsFormulas with polyatomics

• What’s the formula for the compound formed from Al+3 and SCN-1?

• The charges must add up to zero, so write the symbols, positive first!

AlSCNAlSCN33

Try a few more:

• Na+1 and OH-1

• K +1 and HCO3-1

• Mg+2 and CO3-2

• Li +1 and NO3-1

• Ca+2 and SO4-2

NaOHNaOH

KHCOKHCO33

MgCOMgCO33

LiNOLiNO33

CaSOCaSO44

These are more challenging:

• Mg+2 and (PO4)-3

• Al+3 and (NO3)-1

• Fe+2 and OH-1

• Hg2+2 and SCN-1

• Mg+2 and HCO3-

• Al+3 and C2O42-

MgMg33(PO(PO44))22

Al(NOAl(NO33))33

Fe(OH)Fe(OH)22

HgHg22(SCN)(SCN)22

Mg(HCOMg(HCO33))22

AlAl22(C(C22OO44))33

Some of the most challenging are

• Zinc + Nitrate ion• Magnesium + Hydroxide ion• Lithium + Carbonate ion• Potassium + Sulfate ion• Calcium + Phosphate ion• Beryllium + Chlorate ion

Zn(NOZn(NO33))22

Mg(OH)Mg(OH)22

LiLi22COCO33

KK22SOSO44

CaCa33(PO(PO44))22

Be (ClOBe (ClO33))22

Naming compounds with polyatomics

• polyatomic ions have names (Table E)

• naming is parallel to binary naming

• positive always written first

• if (+)’ve ion is a metal, check to see how many oxidation states it has – if > 1 then name must have roman numeral

• if (–)’ve is polyatomic - 2nd part of name is name of polyatomic (don’t modify ending)

Name the following

• NaOHNaOH• KHCOKHCO33

• LiNOLiNO33

• CaSOCaSO44

• Al(NOAl(NO33))33

• Fe(OH)Fe(OH)22

• CuSOCuSO44

• CuSCNCuSCN

Sodium hydroxideSodium hydroxide

Potassium hydrogen carbonatePotassium hydrogen carbonate

Lithium nitrateLithium nitrate

Calcium sulfateCalcium sulfate

Aluminum nitrateAluminum nitrate

Iron (II) hydroxideIron (II) hydroxide

Copper (II) sulfateCopper (II) sulfate

Copper (I) thiocyanateCopper (I) thiocyanate

Summary for Binary Ionic Summary for Binary Ionic CompoundsCompounds

• Compounds are electrically neutral

• Formula: positive first

• If metal has more than 1 oxidation state, name has roman numeral

• Name = metal + stem of nonmetal + ide