1 Nomenclature Chapter 5
2 Common Names - Exceptions H 2 O = water, steam, ice NH 3 = ammonia CH 4 = methane NaCl = table salt C 12 H 22 O 11 = table sugar
3 Naming Starts with Classifying Compounds Binary Compounds = only 2 elements HCl NaBr Fe 2 O 3 CH 4 Compounds containing polyatomic ions (NH 4 ) 3 PO 4 Ca(MnO 4 ) 2 Acids = formula often starts with H HCl H 2 SO 4 HNO 3
4 Classifying Binary Compounds Compounds containing a metal and a nonmetal are binary ionic –Type I = metal cation can only have one charge –Type II = metal cation can have different charges Compounds containing two nonmetals –Type III Compounds containing H and a nonmetal = Acids
5 Metal Cations Type I –Metals that can only have one possible charge –Determine charge by position on the Periodic Table –AlCl 3, BaO, Ca 3 N 2 Type II –Metals that can have more than one possible charge –Determine metal cation’s charge from the charge on anion –FeCl 2, FeCl 3 CuI, CuI 2
6 Table 5.1: Common Simple Cations and Anions
7 Type I Binary Ionic Compounds Contain Metal Cation + Nonmetal Anion Metal listed first in formula & name Name metal cation first, name nonmetal anion second Simple metal cation name is the metal name –simple metals are Groups 1A, 2A and Al, Ag, Ga & In Nonmetal anion named by changing the ending on the nonmetal name to -ide
8 Type I Binary Ionic Compound Examples –CaS –Calcium sulfide –AlCl 3 –Aluminum chloride –Rb 2 O –Rubidium oxide –SrI 2 –Strontium iodide
9 Type II Binary Ionic Compounds Contain Metal Cation + Nonmetal Anion Metal listed first in formula & name Name metal cation first, name nonmetal anion second Metal cation name is the metal name followed by a Roman Numeral in parentheses to indicate its charge –Determine charge from anion charge –Common Type II cations in Table 5.2 Nonmetal anion named by changing the ending on the nonmetal name to -ide
10 IonSystematic NameOld Name Fe 3+ Iron(III)Ferric Fe 2+ Iron(II)Ferrous Cu 2+ Copper(II)Cupric Cu + Copper(I)Cuprous Co 3+ Cobalt(III)Cobaltic Co 2+ Cobalt(II)Cobaltous Sn 4+ Tin(IV)Stannic Sn 2+ Tin(II)Stannous Pb 4+ Lead(IV)Plumbic Pb 2+ Lead(II)Plumbous Hg 2+ Mercury(II)Mercuric Hg 2 2+ Mercury(I)Mecurous
11 Determining the Charge on a Cation – Au 2 S 3 ¬Determine the charge on the anion Au 2 S 3 - the anion is S, since it is in Group 6A, its charge is -2 Determine the total negative charge since there are 3 S in the formula, the total negative charge is -6 ®Determine the total positive charge since the total negative charge is -6, the total positive charge is +6 ¯Divide by the number of cations since there are 2 Au in the formula & the total positive charge is +6, each Au has a +3 charge Au 2 S 3 = gold(III) sulfide
12 Type II Binary Ionic Compound Example –CuCl –Copper(I) chloride –CoBr 2 –Cobalt(II) bromide –PbO 2 –Lead(IV) oxide –Hg 2 S –Mercury(I) sulfide
13 Figure 5.1: A flow chart for naming binary compounds.
14 Type III - Binary Compounds of 2 Nonmetals Name first element in formula first, use the full name of the element Name the second element in the formula as if it were an anion –However, remember these compounds do not contain ions! Use a prefix in front of each name to indicate the number of atoms Never use the prefix mono- on the first element
15 Prefixes Drop last “a” in the prefix if the name begins with vowel octa-8 hepta-7 hexa-6 penta-5 tetra-4 tri-3 di-2 mono- (not used on first nonmetal) 1 PrefixSubscript
16 Type III Binary Compounds –BF 3 –Boron trifluoride –NO –Nitrogon monoxide –N2O5–N2O5 –Dinitrogen pentoxide –CCl 4 –Carbon tetrachloride
17 Compounds Containing Polyatomic Ions Polyatomic ions are charged entities that contain more than one atom –Must memorize name, formula and charge –Look for Patterns!! Polyatomic compounds contain one or more polyatomic ions Name polyatomic compounds by naming cation and anion –Non-polyatomic ions named like Type I and II Polyatomic Acids contain H + and a polyatomic anion
18 Table 5.4: Names of Common Polyatomic Ions
19 Na 2 SO 4 Sodium sulfate KH 2 PO 4 Potassium dihydrogen phosphate Fe(NO 3 ) 3 Iron(III) nitrate Mn(OH) Manganese(II) hydroxide KMnO 4 Potassium permanganate (NH 4 ) 2 Cr 2 O 7 Ammonium dichromate Cu(NO 2 ) 2 Copper(II) nitrite CsClO 4 Cesium perchlorate Compounds with Polyatomic Ions
20 Patterns for Polyatomic Ions ¬Elements in the same column on the Periodic Table form similar polyatomic ions –same number of O’s and same charge ClO 3 - = chlorate BrO 3 - = bromate If the polyatomic ion starts with H, add hydrogen- before the ions name and add 1 to the charge CO 3 2- = carbonate HCO 3 - = hydrogen carbonate
21 Patterns for Polyatomic Ions -ate ion –chlorate = ClO 3 - -ate ion plus 1 O same charge, per- prefix –perchlorate = ClO 4 - -ate ion minus 1 O same charge, -ite suffix –chlorite = ClO 2 - -ate ion minus 2 O same charge, hypo- prefix, - ite suffix –hypochlorite = ClO -
22 Acids Contain H + cation and anion Binary acids have H + cation and a nonmetal anion Oxyacids have H + cation and a polyatomic anion
23 Table 5.5: Names of Acids that Do Not Contain Oxygen
24 AcidName HNO 3 Nitric acid HNO 2 Nitrous acid H 2 SO 4 Sulfuric acid H 2 SO 3 Sulfurous acid H 3 PO 4 Phosphoric acid HC 2 H 3 O 2 Acetic Acid
25 Figure 5.3: A flow chart for naming acids
26 Writing the Formulas from the Names For Type III compounds, use the prefixes to determine the subscripts For Type I, Type II, polyatomic Compounds and Acids –Determine the ions present –Determine the charges on the cation and anion –Balance the charges to get the subscripts
27 Potassium hydroxide KOH Sodium carbonate Na 2 CO 3 Nitric acid HNO 3 Cobalt(II) nitrate Co(NO 3 ) 2 Diphosphorous pentoxide P 2 O 5 Ammonium sulfate (NH 4 ) 2 SO 4 Disulfur dichloride S 2 Cl 2 Rubidium peroxide Rb 2 O 2