Chapter 9 Chemical Names and Formulas

1. Chapter 9Chemical Names and Formulas Hingham High School Mr. Dan Clune

2. Section 9.1Naming Ions

3. Monatomic Ions Ions consisting of a single atom with a positive or negative charge.

4. Naming ions • Two methods if more than one charge is possible: 1. Stock system – uses roman numerals in parenthesis to indicate the numerical value. 2. Classical method – uses root word with suffixes (-ous, -ic) • Does not give true value.

5. Naming ions • We will use the Stock system. • Cation- if the charge is always the same (Group A) just write the name of the metal.

6. Naming Cations • Group 1A has a 1+ charge K1+→ Potassium Ion • Group 2A has a 2+ charge Mg2+→ Magnesium Ion • Group 3A has a 3+ charge Al2+→ Aluminum Ion

7. Naming ions • Transition metals can have more than one type of charge. • Indicate the charge with roman numerals in parenthesis. (Table 9-2, p.255)

8. Naming Cations Transition Elements Transition Elements can have more than one Oxidation Number. Iron can have 2+ or 3+ charges Fe2+→ Iron(II) Ion Fe3+→ Iron(III) Ion

9. Sodium Ion • Calcium Ion • Aluminum Ion • Copper(I) Ion • Copper(II) Ion • Lead(II) Ion • Lithium Ion Name these • Na1+ • Ca2+ • Al3+ • Cu+ • Cu2+ • Pb2+ • Li1+

10. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluorine

11. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluorin

12. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluori

13. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluor

14. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluori

15. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluorid

16. Naming Anions • Anions are always the same charge • Change the element ending to – ide • F1- Fluoride

17. Name these • Chloride • Nitride • Bromide • Oxide • Gallium • Cl1- • N3- • Br1- • O2- • Ga3+

18. Write these • Sulfide ion • Iodide ion • Phosphide ion • Strontium ion • S2- • I1- • P3- • St2+

19. +e- +e- Cl Cl- F F- +e- Br Br- Halide Ions The ions that are produced when atoms of chlorine and other halogens gain electrons.

20. Exceptions: • Some of the Transition Metals have only one ionic charge: • Do not use roman numerals for these: • Silver is always 1+ (Ag1+) • Cadmium and Zinc are always 2+ (Cd2+ and Zn2+)

21. Polyatomic Ions • Groups of atoms that stay together and have a charge. • Most Polyatomic Ions end in: • “ite” • “ate”

22. [ ]1- O N O Nitrite

23. [ ]1- O N O O Nitrate

24. Polyatomic ions • Acetate C2H3O21- • Nitrate NO31- • Nitrite NO21- • Hydroxide OH1- • Cyanide CN1- • Permanganate MnO41-

25. Sulfate SO42- Sulfite SO32- Carbonate CO32- Chromate CrO42- Polyatomic ions

26. Dichromate Cr2O72- Phosphate PO43- Phosphite PO33- Ammonium NH41+ Polyatomic ions

27. Adding Hydrogen to aPolyatomic Ion H+ + C032-→ HCO3- Hydrogen + Carbonate → Hydrogen Carbonate H+ + P043-→ HPO42- Hydrogen + Phosphate → Hydrogen Phosphate

28. H+ + HPO42-→ H2PO4- Hydrogen + Hydrogen → Dihydrogen Phosphate Phosphate

29. Common Anions

31. Homework Section 9-1 Review Practice Problems Due: 12/13/05

32. Section 9-2 Naming and Writing Formulas for Ionic Compounds

33. Naming Binary Ionic Compounds • Binary Compounds - 2 elements. • Ionic - a cation and an anion. • To write the names, just name the two ions.

34. Naming Binary Ionic Compounds • Easy with Representative elements (which are Group A elements) • NaCl = Na1+Cl1- = Sodium Chloride • MgBr2 = Mg2+Br1-= Magnesium Bromide

35. Naming Binary Ionic Compounds • The problem comes with the transition metals. • Need to figure out their charges. • The compound must be neutral. • same number of + and – charges. • Use the anion to determine the charge on the positive ion.

36. Naming Binary Ionic Compounds • Write the name of CuO • Need the charge of Cu • Cu?O2- • copper must be 2+ • Copper(II) Oxide

37. Naming Binary Ionic Compounds • Name CoCl3 CoCl3 • Cl is 1- and there are three of them = 3- • Co must be 3+ • Cobalt (III) Chloride • Reverse Criss-Cross

38. Naming Binary Ionic Compounds • Write the name of Cu2S. Cu2S • Since S is 2-, the Cu2 must be 2+, so each one is 1+. • Copper(I) Sulfide

39. Naming Binary Ionic Compounds • Fe2O3 • Each O is 2- 3 x -2 = -6 • 2 Fe must = 6+, so each is 3+. • Iron(III) Oxide

40. Naming Binary Ionic Compounds Write the names of the following • KCl • Na3N • CrN • Sc3P2 Potassium Chloride Sodium Nitride Chromium(III) Nitride Scandium(II) Phosphide

41. Naming Binary Ionic Compounds • PbO • PbO2 • Na2Se Write the names of the following Lead(II) Oxide Lead(IV) Oxide Sodium Selenide

42. Ternary Ionic Compounds • Consist of polyatomic ions • At least three elements • Name the ions • NaNO3 • CaSO4 • (NH4)2C2O4 Sodium Nitrate Calcium Sulfate Ammonium Oxalate

43. Ternary Ionic Compounds • Fe(OH)3 • NiPO4 Iron(III) Hydroxide Nickel(III) Phosphate • CuSO3 Copper(II) Sulfite

44. Writing Formulas • The charges have to add up to zero. • Get charges on pieces. • Cations from name on table. • Anions from table or polyatomic. • Balance the charges by adding subscripts. • Put polyatomics in parenthesis.

45. Writing Formulas • Write the formula for calcium chloride. • Calcium is Ca2+ • Chloride is Cl1- • Ca2+ Cl1- would have a 1+ charge. • Need another Cl1- • Ca2+ Cl21- (use criss-cross method)

46. Cl2 Ca Criss Cross MethodCalcium Chloride Cl Ca - 2+

47. N Cu3 Criss Cross MethodCopper(I) Nitride N Cu 3- +

48. Criss Cross MethodCalcium Phosphate PO4 2+ 3- Ca ( ) PO4 Ca3 2

49. Write the formulas for these • lithium sulfide • tin(II) oxide • tin(IV) oxide • magnesium fluoride • Li2S • SnO • Sn2O • MgF2

50. Write the formulas for these • CuSO4 • FeP • Ga(NO3)3 • Fe2S3 • copper(II) sulfate • iron(III) phosphide • gallium nitrate • iron(III) sulfide