Section 2.8 Naming Simple Compounds Return to TOC 10/14/2015 Chemistry 1 Vocabulary - Review Q: What is a cation? A: A positive ion formed by a metal Examples: Na + Ca 2+ Al 3+ Q: What is an anion? A: A negative ion formed by a nonmetal. Examples: H - F - O 2- P 3- Q: What is a polyatomic ion? A: A group of charged atoms NH 4 + SO

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Attraction between + ions and - ions Electrons go from metals to nonmetals electron transfer metal nonmetal ion + ion – Electrons lost = Electrons gain NOTE: the net charge on the compound is zero 2

Section 2.8 Naming Simple Compounds Return to TOC 3 Formation of Ionic Compounds

Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding What happens when an atom of sodium reacts with an atom of chlorine? NaNa + + 1e- Cl + 1e-Cl - Na + Cl + 1e- Na + Cl - + 1e- 4

Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding We write Na + Cl - as simply NaCl The ionic compound is neutral – this means the net (overall) charge is = 0. Now let’s try for cesium reacting with sulfur. 5

Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding CsCs + + 1e- S + 2e-S 2- Cs + S + 2e-Cs + S e- This equation is not balanced. What must be done to correct this? Solution: 1. Write the symbol for each ion present 2.Make sure you include the charge of each ion 6

Section 2.8 Naming Simple Compounds Return to TOC Writing a Formula Write the formula for the ionic compound that will form between Ba 2+ and Cl . Solution: 1. Balance charge with + and – ions 2. Write the positive ion of metal first, and the negative ion Ba 2+ Cl  3. Write the number of ions needed as subscripts BaCl 2 (NOTE WE CRISSCROSSED THE CHARGES ) 7

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds--Example: Sodium and oxygen react 1.You have to balance the charges. 2.You do this by criss-crossing the value of the charge (not the + or -) Sodium oxide Na + O 2- Na 2 O we do not write the 1 as a subscript 8

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Lithium iodide Li + I – LiI 9

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Magnesium oxide Mg 2+ O 2- Mg 2 O 2 MUST be reduced to MgO 10

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Let’s try a few: Barium nitride Ba 3 N 2 Aluminum oxide Al 2 O 3 Cesium iodide CsI Sodium fluoride NaF Strontium bromide SrBr 2 11

Section 2.8 Naming Simple Compounds Return to TOC Learning Check Write the correct formula for the compounds containing the following ions: A. Na +, S 2- B. Al 3+, Cl - C. Mg 2+, N 3- 12

Section 2.8 Naming Simple Compounds Return to TOC Solution A. Na +, S 2- Na 2 S B. Al 3+, Cl - AlCl 3 C. Mg 2+, N 3- Mg 3 N 2 13

Section 2.8 Naming Simple Compounds Return to TOC 14 Binary Compounds  Composed of two elements  Ionic and covalent compounds included Binary Ionic Compounds  Metal—nonmetal Binary Covalent Compounds  Nonmetal—nonmetal Naming Compounds

Section 2.8 Naming Simple Compounds Return to TOC 15 Binary Compounds  Composed of two elements Binary Ionic Compounds  Metal—nonmetal Binary Covalent Compounds  Nonmetal—nonmetal

Section 2.8 Naming Simple Compounds Return to TOC 16 Binary ionic compounds contain positive cations and negative anions.  Type I compounds Metal present forms only one cation.  Type II compounds Metal present can form 2 or more cations with different charges.

Section 2.8 Naming Simple Compounds Return to TOC 17 1.Contain 2 different elements 2.The cation is always named first and the anion second. 2.A cation has same name as element. Examples: Ca 2+ calcium Al 3+ aluminum Na + sodium 3.A anion has the same name as the element name with adding –ide to the end. Examples: Cl - chloride S 2- sulfide P 3- phosphide Binary Ionic Compounds (Type I monatomic cations & anions)

Section 2.8 Naming Simple Compounds Return to TOC 18 Common Simple Cations and Anions

Section 2.8 Naming Simple Compounds Return to TOC 19 1.The cation is always named first and the anion second. 2.A simple cation takes its name from the name of the element. 3.A simple anion is named by taking the first part of the element name (the root) and adding –ide. Rules for Naming Type I Ionic Compounds

Section 2.8 Naming Simple Compounds Return to TOC 20 Examples: KClPotassium chloride MgBr 2 Magnesium bromide CaOCalcium oxide Binary Ionic Compounds (Type I)

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Now let us put it all together: Na 3 N Cation: sodium Anion: nitride Compound: Sodium nitride 21

Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds BaO Cation:barium Anion:oxide Compound: barium oxide 22

Section 2.8 Naming Simple Compounds Return to TOC Naming Binary Ionic Compounds (Type I) SUMMARY - Name the metal first, then the nonmetal with ending changed to -ide. Examples: NaClsodium chloride ZnI 2 zinc iodide Al 2 O 3 aluminum oxide KClPotassium chloride MgBr 2 Magnesium bromide CaOCalcium oxide 23

Section 2.8 Naming Simple Compounds Return to TOC 24 Exercise What is the name of the compound SrBr 2 ? a)strontium bromine b)sulfur bromide c)strontium dibromide d)strontium bromide

Section 2.8 Naming Simple Compounds Return to TOC Learning Check Complete the names of the following type I binary compounds: Na 3 Nsodium ________________ KBrpotassium________________ Al 2 O 3 aluminum ________________ MgS_________________________ 25

Section 2.8 Naming Simple Compounds Return to TOC Solution Complete the names of the following binary compounds: Na 3 Nsodium nitride KBrpotassium bromide Al 2 O 3 aluminum oxide MgSmagnesium sulfide 26

Section 2.8 Naming Simple Compounds Return to TOC 27 Binary Ionic Compounds (Type II) Metals in these compounds can form more than one type of positive charge. Charge on the metal ion must be specified. Roman numeral indicates the charge of the metal cation. Transition metal cations usually require a Roman numeral.

Section 2.8 Naming Simple Compounds Return to TOC 28 Metals in these compounds form more than one type of positive charge. Charge on the metal ion must be specified. Roman numeral indicates the charge of the metal cation. Transition metal cations that form 2 or more positive ions require a Roman numeral. Binary Ionic Compounds (Type II) 1+ or 2+ ____________________ 2+ or 3+ Cu+, Cu2+ Fe2+, Fe3+ copper(I) ion iron(II) ion copper (II) ion iron(III) ion

Section 2.8 Naming Simple Compounds Return to TOC 29 Common Type II Cations

Section 2.8 Naming Simple Compounds Return to TOC 30 1.The cation is always named first and the anion second. 2.Because the cation can assume more than one charge, the charge is specified by a Roman numeral in parentheses. Rules for Naming Type II Ionic Compounds

Section 2.8 Naming Simple Compounds Return to TOC 31 Examples: CuBrCopper(I) bromide FeSIron(II) sulfide PbO 2 Lead(IV) oxide Binary Ionic Compounds (Type II)

Section 2.8 Naming Simple Compounds Return to TOC Binary Ionic Compounds (Type II) Use a roman number after the name of a metal that forms two or more ions (note compound is neutral) Example: FeCl 3 (Fe 3+ ) iron (III) chloride CuCl (Cu + ) copper (I) chloride SnF 4 (Sn 4+ ) tin (IV) fluoride PbCl 2 (Pb 2+ )lead (II) chloride Fe 2 S 3 (Fe 3+ )iron (III) sulfide 32

Section 2.8 Naming Simple Compounds Return to TOC 33 Exercise What is the name of the compound CrO 2 ? a)chromium oxide b)chromium(II) oxide c)chromium(IV) oxide d)chromium dioxide

Section 2.8 Naming Simple Compounds Return to TOC 34 Exercise What is the correct name of the compound that results from the most stable ion for sulfur and the metal ion that contains 24 electrons? a)iron(III) sulfide b)chromium(II) sulfide c)nickel(III) sulfate d)iron(II) sulfide

Section 2.8 Naming Simple Compounds Return to TOC Learning Check Complete the names of the following binary compounds with variable metal ions: FeBr 2 iron (_____) bromide Cu 2 Ocopper (_____) oxide SnCl 4 ___(_____ ) ______________ Fe 2 O 3 ________________________ CuS________________________ 35

Section 2.8 Naming Simple Compounds Return to TOC Solution Complete the names of the following binary compounds with variable metal ions: FeBr 2 iron ( II ) bromide Cu 2 Ocopper ( I ) oxide SnCl 4 tin (IV) chloride Fe 2 O 3 iron (III) oxide CuScopper (II) sulfide 36

Section 2.8 Naming Simple Compounds Return to TOC Learning Check Name the following compounds: A. CaO B. SnCl 4 C. Co 2 O 3 37

Section 2.8 Naming Simple Compounds Return to TOC Solution Name the following compounds: A. CaOcalcium oxide B. SnCl 4 tin(IV) chloride C.Co 2 O 3 cobalt (III) oxide 38

Section 2.8 Naming Simple Compounds Return to TOC 39 Polyatomic ions are charged entities composed of several atoms bound together. They have special names and must be memorized. (see Table 2.5 on pg. 62 in text). Examples of compounds containing polyatomic ions: NaOHSodium hydroxide Mg(NO 3 ) 2 Magnesium nitrate (NH 4 ) 2 SO 4 Ammonium sulfate

Section 2.8 Naming Simple Compounds Return to TOC 40 Names of Common Polyatomic Ions

Section 2.8 Naming Simple Compounds Return to TOC 41 Naming ionic compounds containing polyatomic ions follows rules similar to those for binary compounds.  Ammonium acetate

Section 2.8 Naming Simple Compounds Return to TOC 42 NaOHSodium hydroxide Mg(NO 3 ) 2 Magnesium nitrate (NH 4 ) 2 SO 4 Ammonium sulfate FePO 4 Iron(III) phosphate Examples

Section 2.8 Naming Simple Compounds Return to TOC 43 Exercise What is the name of the compound KClO 3 ? a)potassium chlorite b)potassium chlorate c)potassium perchlorate d)potassium carbonate