N AMING C OMPOUNDS

N AMING I ONS AND I ONIC C OMPOUNDS Formulas for ionic compounds are generally empirical formulas. Ionic compounds are electronically neutral.

Al 3+ O 2– Al 2 O 3 In order for ionic compounds to be electronically neutral, the sum of the charges on the cation and anion in each formula must be zero. Aluminum oxide: Sum of charges:2(+3) + 3(–2) = 0 Formulas of Ionic Compounds

N AMING I ONS AND I ONIC C OMPOUNDS To name ionic compounds: 1) Name the cation  omit the word ion  use a Roman numeral if the cation can have more than one charge 2) Name the anion  omit the word ion Examples: NaCN sodium cyanide FeCl 2 iron(II) chloride FeCl 3 iron(III) chloride

TiSe __________________________________ 2) Cu2O _________________________________ 3) V3P5 __________________________________ 4) Co(ClO3)3 ______________________________ 5) Pb(SO4)2 ______________________________ 6) CuCrO4 ________________________________ 7) (NH4)3PO4 _____________________________ 8) Cu(NO2)2 ______________________________ 9) KCN __________________________________ 10) Zn3N2 _________________________________

1)sodium chloride 2) potassium bromide 3) calcium oxide 4) magnesium sulfide 5) zinc chloride 6) sodium sulfide 7) strontium fluoride 8) lithium oxide 9) potassium nitride 10) sodium phosphide 11) aluminum chloride

W RITING C OVALENT C OMPOUNDS Made of two anions (2 nonmetals or 1 nonmetal & 1 polyatomic ion) Identify the less electronegative element 1 st (trend = less EN is the one farthest left & farthest down on Periodic Table) The 1 st nonmetal is just given the name as found on the Periodic Table (just like ionic) The 2 nd nonmetal ending is changed to –ide (just like ionic…don’t change polyatomics) Difference = numerical prefixes are used to express how many of each nonmetal are present

W RITING C OVALENT C OMPOUNDS ( CONT.) You never use “criss-cross” method The only time you do not use a prefix is when there is only one of the first nonmetal. NumberPrefix 1Mono 2Di 3Tri 4Tetra 5Penta 6Hexa 7Hepta 8Octa 9Nona 10Deca

C OVALENT C OMPOUND P RACTICE SO 2 N2ON2O NO 2 CCl 4 Cl 2 O 7 PCl 3 SF 6 Si 3 N 4 N(BrO 3 ) 5 H2OH2O Sulfur Dioxide Dinitrogen Monoxide Nitrogen Dioxide Carbon Tetrachloride Dichlorine Heptaoxide Phosphorus Trichloride Sulfur Hexaflouride Trisilicon Tetranitride Nitrogen Pentabromate Water - can use common name

C OVALENT C OMPOUND P RACTICE Phosphorus Trioxide Dinitrogen Pentacarbide Tellurium Noniodide Carbon Monoxide Selenium Heptaflouride Tetraphosphorous Decoxide Arsenic Hexabromide Silicon Dichloride PO 3 N2C5N2C5 TeI 9 CO SeF 7 P 4 O 10 AsBr 6 SiCl 2