1. 1 Quiz on _________ Single Daily Grade

3. 3 Table of Contents Difference between Molecular and Ionic Compounds Acids Naming Molecular Compounds Formulas for Molecular Compounds Charges and rules for ions Naming/Formulas for Ions Naming Binary Ionic Compounds Formulas for Binary Ionic Compounds Naming ionic compounds with polyatomics Formulas for ionic compounds with polyatomics

4. 4

5. 5 A. Definition Remember, a compound consists of 2 or more elements chemically bonded together. It is always neutral. EX: H 2 O, NaCl, Sb 3 (PO 4 ) 5

6. 6 There are two main ways to name chemical compounds. However, before you can even think about naming the compound you must decide what kind of compound you have. Do you have a covalent or ionic compound? We already learned this using the terms molecule and formula unit.

7. 7 Most formulas are written with the elements listed from left to right on the periodic table

8. 8 What do you remember about the difference between a molecule and a formula unit?

9. B. Types of Compounds 2 types of chemical compounds

10. 10 Samples Ionic Compounds Rock salt (NaCl) Calcium Carbonate (CaCO 3 ) Potassium Nitrate (KNO 3 ) Molecular Compounds Sugar (C 12 H 22 O 11 ) Methane gas (CH 4 ) What’s the difference?

11. 11 1. Ionic Compound: Ionic Compound: a compound that is formed by ions of opposite charges. It is held together by an ionic (transfer electrons) bond and usually contains a metal and nonmetal. EX: NaCl, Sb 3 (PO 4 ) 5 smallest unit is called a formula unit

12. 12 2. Molecular or Covalent Compound: Molecular or Covalent compound: consists of only nonmetal atoms and is held together by covalent (share electrons) bonds EX: H 2 O, C 8 H 18 smallest unit is called a molecule

13. 13 How can I tell!? Look for a metal. If there’s a metal, it’s an ionic compound

14. 14 Practice 1. Determine whether the following are ionic or molecular covalent compounds a. N 2 O 5 b. PbNO 5 c. KFd. AgCl e. PCl 3 ionic molecular ionic KFKF AgCl PbNO 5

15. 15 Acids: have a formula that starts with hydrogen You need to know the names and formulas for the following acids: Acid NameFormula hydrochloric acidHCl nitric acidHNO 3 sulfuric acidH 2 SO 4 phosphoric acidH 3 PO 4 Note: all acids start with “H” in their chemical formulas and include the word “acid” in their names.

16. II. Molecular Compounds (aka Covalent Compounds aka Molecules)

17. 17 Molecular Compounds = share electrons H O H2OH2O H

18. 18 A. Binary Molecular Compounds Molecular compounds DO NOT contain a metal atom Molecular compound contain covalent bonds We use prefixes to name molecular, ONLY MOLECULAR, compounds

19. 19 How do I distinguish between the bikes? unicycle bicycle tricycle

20. 20 We use prefixes to help distinguish molecular compounds. PrefixNumber of Atoms mono1 di2 tri3 tetra4 penta5 hexa6 hepta7 octa8 nona9 deca10

21. 21 Why have prefixes? Nitrogen bonds to Oxygen in more than one way Ex:N 2 O, NO 2, N 2 O 2, N 2 O 5

22. 22 Examples: Formula: CO Name: Formula: N 2 O Name: carbon monoxide dinitrogen monoxide

23. 23 a. Naming binary molecular compounds: FIRST ELEMENT IN THE FORMULA –keeps its full elemental name –Add prefixes to signify the number of that specific kind of atom ONLY if there is more than one of the atoms. DON’T USE MONO ON THE FIRST SYMBOL SECOND ELEMENT IN THE FORMULA –The second element name ALWAYS gets a prefix –Keep the first syllable of the elemental name and change the suffix to “ide”.

24. 24 Practice: Formula: CO 2 name: Formula: BF 3 name: Formula: Cl 2 O name: Formula: P 2 S 5 name: Carbon dioxide Boron trifluoride Dichlorine monoxide Diphosphorus pentasulfide

25. 25 B. Converting a name to a formula: This exercise is very simple if you have memorized the element symbols and the prefixes. Just go backwards from what we just did.

26. 26 Examples: Formula: Name: carbon tetrachloride. Formula: Name: dihydrogen monofluoride CCl 4 H2FH2F

27. 27 Practice: Formula: H 2 O name: Dihydrogen monoxide Formula: name: Nitrogen pentoxide Formula: name: CarbonTetrafluoride Formula: name: Silicon Dioxide NO 5 CF 4 SiO 2

28. 1+ 2+3+3-2-1-

29. 29 III. Naming ions 1. Monatomic Cations (+ ions) Monatomic cations are named by writing the element’s name and then “ion” after it. EX: Ca 2+ Na + Oneatom + Sodium ion Calcium ion

30. 30 a. Monatomic Cations (Transition + PASS + Z.A.C Elements ) Most transition metals and “P.A.S.S” elements need Roman Numerals Zinc (Zn), Silver (Ag), and Cadmium (Cd) are transition metals that DO NOT need Roman Numerals “Z.A.C Elements” Roman Numerals 1-5: I, II, III, IV, V

31. 31 More than just “Iron ion” EX:Fe 2+ Fe 3+ Iron (III) ionIron (II) ion

32. 32 Transition Metals need R.N. 1. Name these ions a. Pb 4+ b. Pb 2+ c. Cu + d. Cu 2+ Lead (IV) ion Lead (II) ion Copper (I) ion Copper (II) ion

33. 33 Examples 1. Name these ions a. Ca 2+ b. Na + c. Fe 4+ d. Zn 2+ Calcium ion Sodium ion Iron (IV) ion Zinc ion

34. 34 b. Monoatomic Anions (- ions) o Monatomic anions are named by changing the suffix to “ide” then adding “ion” after it.

35. 35 Cation or Anion? Carbon can act as a cation (carbon ion) or as an anion (carbide ion). It just depends if it is in the beginning or the end of the compound’s formula Hydrogen can also act as a cation (hydrogen) or as an anion (hydride). It just depends if it is in the beginning or the end of the compound’s formula. Don’t forget it is a non-metal.

36. Complete the chart below ElementSymbol Oxidation number Anion name ChlorineCl - Chloride ion BromineBr - Bromide ion Oxygen S 2- Phosphide ion N 3- Sulfur O 2- -2 Oxide ion -2Sulfide ion Phosphorus P 3- -3 Nitrogen-3Nitride ion

37. 37 Summary List the elements that need Roman Numerals List the transition metals that don’t need Roman Numerals Transition metals, PASS elements (Pb, As, Sn, Sb) Zn, Ag, Cd (Z.A.C elements)

38. 38 Always need roman numerals 1+ 2+3+3-2-1- Tips TM (Except ZAC) and PASS need Roman Numerals All metals are +; all non-metals are - Anions end in -ide Anions: Change Suffix to -ide Zn 2+ Cd 2+ Ag + always

39. 39 c. Polyatomic Cations A polyatomic ion is a group of covalently bonded atoms that have an overall charge Example NH 4 + = ammonium.

40. 40 d. Polyatomic Anions This means the anion is a COVALENTLY BONDED GROUP of atoms that have a – charge. They are EASY to deal with in naming and formula writing if you think of them as ONE UNIT that can not be altered in any way.

41. 41 Example: Use the back of your periodic table to help you identify polyatomic anions

42. 42 Flip over your PT and let’s practice 1. Name these ions a. CO 3 2- b. OH - c. NO 3 - d. SO 4 2- e. PO 4 3- carbonate hydroxide nitrate sulfate phosphate

43. 43 There is only a handful you NEED TO MEMORIZE. Here they are: +1 charge-1 charge-2 charge-3 charge Ammonium ion NH 4 + Nitrate ion NO 3 - Sulfate ion SO 4 2- Phosphate ion PO 4 3- Hydroxide OH - Carbonate CO 3 2- Learn to effectively use the back of your periodic table

44. 44 IV. Binary Ionic Compounds a. Naming Binary Ionic Compounds Ionic Compounds are made of a cation and anion pair. You already know how to name the ions. Just put the names together and leave off the word ion. Don’t forget Roman Numerals!

45. 45 Ionic Compounds = transfer of electrons Na Cl + - NaCl Is formed

46. 46 a. Naming Binary Ionic Compounds FormulaIonsIon namesCompound name AlN Al 3+ N 3- Aluminum ion Nitride ion Na 2 0 Na + O 2- Sodium ion Oxide ion FeO Fe 2+ O 2- Fe 2 O 3 Fe 3+ O 2- Iron (II) ion Oxide ion Iron (III) ion Oxide ion Aluminum nitride Sodium oxide Iron (II) oxide Iron (III) oxide

47. 47 Ex. Name FeS Iron Sulfide Iron (II) sulfide NOT

48. 48 Remember to add a Roman Numeral for the cations that need one One trick to determine the Roman Numeral: 1. Add up your total negative charges 2. Divide the above number by the total number of metal ions 3. Change to a Roman Numeral

49. 49 Ex. Name FeS Total neg. charges: 2- 2/1 (Fe) = 2 1. Add up your total negative charges 2. Divide the above number by the total number of metal ions 3. Change to a Roman Numeral Iron (II) Sulfide

50. 50 Ex. Name Fe 2 O 3 Total neg. charges: 6- 6/2 (Fe) = 3 Iron (III) Oxide

51. 51 Practice 1. Name the following compounds a. ZnS b. K 3 N c. BaO d. CaBr 2 e. SnF 2 Zinc sulfide Potassium nitride Barium oxide Calcium bromide Tin (II) fluoride

52. 52 Practice 1. Name the following compounds f. CaO g. AlF 3 h. CuI 2 i. Cu 2 Se j. Hg 2 O Calcium oxide Aluminum fluoride Copper (II) iodide Copper (I) Selenide Mercury (I) Oxide

53. 53 b. Writing Formulas for Binary Ionic Compounds Remember, a compound must be electrically neutral. Therefore, the total positive charge of the cation must equal the total negative charge of the anion.

54. 54 EX:calcium chloride Ca 2+ Cl - To make a neutral compound Ca 2+ Cl - Cl- +2 -2 CaCl 2

55. 55 To write a formula for a binary ionic compound 1.Write the ions that are named in the compound showing oxidation numbers. 2. Determine how many of each ion you need to make a neutral compound. 3. To write the formula, list the metal symbol first and then the anion symbol, adding subscripts to indicate how many of each ion there is in the formula 4. Make sure the formula has the lowest whole number ratio. Note: you never write a 1 subscript; it is understood.

56. 56 EX: write the formula for aluminum fluoride Al +3 F - NOTE: You never include oxidation numbers in the chemical formula of a compound. Formula: AlF 3 F-F- F-F- +3 -3

57. 57 Practice – only do a-c 1. Write chemical formulas for the following: a. strontium phosphide b. potassium sulfide c. iron (II) chloride Sr 3 P 2 K2SK2S FeCl 2

58. 58 The Criss-Cross Method One easy way to figure out the formula of an ionic compound is to swap the oxidation number of each ion and use them as subscripts. (without the charge) the formula must be in the lowest whole number ratio

59. 59 Na S Just Watch!! sodium sulfide 12 + - 1’s are understood Na 2 S

60. 60 Fe Br Ex: Write the formula for iron (III) bromide 3 + - FeBr 3

61. 61 Mg S Ex: Write the formula for magnesium sulfide 22 + - Note: if both ox #’s are equal, you don’t need to use the crisscross method, just show 1 ion of each.

62. 62 Magnesium Sulfide MgS (not Mg 2 S 2 )

63. 63 Pb S Note: show the formula with the lowest whole number ratio. EX: write the formula for lead (IV) sulfide 42 + -

64. 64 Criss Cross Method Pb 2 S 4 PbS 2

65. 65 Finish the Practice Box 1. Write chemical formulas for the following: d. antimony (V) nitride e. iron (III) chloride f. Calcium bromide CaBr 2 FeCl 3 Sb 3 N 5

66. 66 Naming Same way as you already learned Use subscripts to show how many of each ion you needed to make a neutral compound Formulas

67. 67 V. Ionic Compounds Containing Polyatomic Ions a. Writing Formulas for Polyatomic Compounds Write formulas for polyatomic ions in the same way. Just remember the polyatomic ion acts as a whole unit and you need to use parentheses if you need more than 1 of them. Note: You never change the formula of a polyatomic ion!

68. 68 EX:calcium nitrate To make a neutral compound Ca 2+ (NO 3 ) - (NO 3 ) - +2 -2 Ca(NO 3 ) 2

69. 69 Ca(NO 3 ) EX: Calcium Nitrate (using the criss cross method) 2 + -

70. 70 Practice 1. Write formulas for the following compounds a. strontium sulfate b. lithium carbonate c. potassium sulfate d. magnesium hydroxide SrSO 4 or Sr(SO 4 ) Li 2 CO 3 or Li 2 (CO 3 ) Mg(OH) 2 K 2 SO 4 or K 2 (SO 4 )

71. 71 Practice 1. Write formulas for the following compounds e. ammonium dichromate f. potassium permanganate g. sodium hypochlorite h. barium sulfite (NH 4 ) 2 Cr 2 O 7 or (NH 4 ) 2 (Cr 2 O 7 ) NaClO or Na(ClO) BaSO 3 or Ba(SO 3 ) KMnO 4 or K(MnO 4 )

72. 72 b. Naming Polyatomic Compounds It is important that you recognize the polyatomic If there are more than 2 elements in the formula, then you know it contains a polyatomic. Only one polyatomic is a cation, ammonium (NH 4 + ) All the rest will come after the metal ion.

73. 73 You name polyatomic compounds just like you would other ionic compounds -- you write the name of each ion. Note: most (not all) polyatomic compounds will end in -ate or -ite.

74. 74 Ex. Name ZnSO 4 Zinc Ex. Name NaOH Sodium Sulfate hydroxide

75. 75 Practice 1. Name these compounds a. CaCO 3 b. KClO c. KMnO 4 calcium carbonate potassium hypochlorite potassium permanganate

76. 76 Practice 1. Name these compounds d. Al(OH) 3 e. Sn 3 (PO 4 ) 2 f. Na 2 CrO 4 aluminum hydroxide tin (II) phosphate sodium chromate