Ionic Compounds: Naming

Naming Binary Ionic Compounds Always name metal (cation, + ion) first 2. Write stem of nonmetal (anion, - ion) 3. Add ending “ide” to nonmetal

Stems of nonmetals Iod Brom Chlor Fluor Hydr is the stem for H Tellur Selen Arsen Sulf Phosph Ox Nitr

The 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 oxide barium sulfide aluminum nitride lithium chloride aluminum selenide sodium qxide potassium nitride magnesium fluoride

Metals with more than 1 oxidation state Use formula to figure out which oxidation # for the metal ion Ex: Fe can be Fe+2 or Fe+3 Name FeO and Fe2O3 two different compounds cannot name both iron oxide every formula has 1 name only

FeO and Fe2O3 FeO 1 O which is -2 so Fe must be +2 Compounds are electrically neutral Oxygen is -2 1 O which is -2 FeO so Fe must be +2 Name: Iron (II) oxide (roman numeral II = charge on Fe)

FeO and Fe2O3 Fe2O3 Compounds are electrically neutral Oxygen is -2 Each Fe is +3 Iron (III) oxide Each O is -2 Fe2O3 There are 3 O’s 3 X (-2) = -6 Total negative charge Total positive charge must be +6

Name the following TiCl3 Mn2O4 Co2O3 PdBr2 AuCl3 MoN MnO TiO Titanium (III) chloride Manganese (IV) oxide Cobalt (III) oxide Palladium (II) bromide Gold (III) chloride Molybdenum (III) nitride Manganese (II) oxide Titanium (II) oxide

POLYATOMIC IONS SO42- CO32- PO43- OH- 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 SO42- CO32- PO43- 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 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! AlSCN3

Try a few more: Na+1 and OH-1 K +1 and HCO3-1 Mg+2 and CO3-2 NaOH 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 KHCO3 MgCO3 LiNO3 CaSO4

These are more challenging: Mg3(PO4)2 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- Al(NO3)3 Fe(OH)2 Hg2(SCN)2 Mg(HCO3)2 Al2(C2O4)3

Some of the most challenging are Zn(NO3)2 Zinc + Nitrate ion Magnesium + Hydroxide ion Lithium + Carbonate ion Potassium + Sulfate ion Calcium + Phosphate ion Beryllium + Chlorate ion Mg(OH)2 Li2CO3 K2SO4 Ca3(PO4)2 Be (ClO3)2

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 more than 1, name must have roman numeral if (–)’ve ion is polyatomic - 2nd part of name is name of polyatomic (don’t modify ending)

Name the following NaOH KHCO3 LiNO3 CaSO4 Al(NO3)3 Fe(OH)2 CuSO4 CuSCN Sodium hydroxide Potassium hydrogen carbonate Lithium nitrate Calcium sulfate Aluminum nitrate Iron (II) hydroxide Copper (II) sulfate Copper (I) thiocyanate

Summary for Binary Ionic Compounds 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