Nomenclature Chapter 5

1. NomenclatureChapter 5

2. Common Names - Exceptions • H2O = water, steam, ice • NH3 = ammonia • CH4 = methane • NaCl = table salt • C12H22O11 = table sugar

3. Naming Starts with Classifying Compounds • Binary Compounds = only 2 elements HCl NaBr Fe2O3 CH4 • Compounds containing polyatomic ions (NH4)3PO4 Ca(MnO4)2 • Acids = formula often starts with H HCl H2SO4 HNO3

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 • AlCl3, BaO, Ca3N2 • Type II • Metals that can have more than one possible charge • Determine metal cation’s charge from the charge on anion • FeCl2, FeCl3 CuI, CuI2

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 • AlCl3 • Aluminum chloride • Rb2O • Rubidium oxide • SrI2 • 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

11. Determining the Charge on a Cation – Au2S3 • Determine the charge on the anion Au2S3 - 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 Au2S3 = gold(III) sulfide

12. Type II Binary Ionic Compound Example • CuCl • Copper(I) chloride • CoBr2 • Cobalt(II) bromide • PbO2 • Lead(IV) oxide • Hg2S • 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. Subscript Prefix 1 mono- (not used on first nonmetal) 2 di- 3 tri- 4 tetra- 5 penta- 6 hexa- 7 hepta- 8 octa- Prefixes • Drop last “a” in the prefix if the name begins with vowel

16. Type III Binary Compounds • BF3 • Boron trifluoride • NO • Nitrogon monoxide • N2O5 • Dinitrogen pentoxide • CCl4 • 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. Na2SO4 Sodium sulfate KH2PO4 Potassium dihydrogen phosphate Fe(NO3)3 Iron(III) nitrate Mn(OH) Manganese(II) hydroxide KMnO4 Potassium permanganate (NH4)2Cr2O7 Ammonium dichromate Cu(NO2)2 Copper(II) nitrite CsClO4 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 ClO3- = chlorate  BrO3- = bromate • If the polyatomic ion starts with H, add hydrogen- before the ions name and add 1 to the charge CO32- = carbonate  HCO3- = hydrogen carbonate

21. Patterns for Polyatomic Ions • -ate ion • chlorate = ClO3- • -ate ion plus 1 O  same charge, per- prefix • perchlorate = ClO4- • -ate ion minus 1 O  same charge, -ite suffix • chlorite = ClO2- • -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

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 Na2CO3 Nitric acid HNO3 Cobalt(II) nitrate Co(NO3)2 Diphosphorous pentoxide P2O5 Ammonium sulfate (NH4)2SO4 Disulfur dichloride S2Cl2 Rubidium peroxide Rb2O2