1. Writing Ionic Formulas Chemical Formulas from Names & Names from Chemical Formulas

2. Basic Principles Formulas show smallest whole-number ratio of ions (posititve and negative) in the substance. Formulas are correct only if total charges of all ions add to zero (bulk matter is electrically neutral). Cations (positive) written and named before anions.

3. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112

4. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +1

5. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +2

6. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +2 for many; some +1, others +3; several vary

7. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112

8. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 -2

9. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 -3

10. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +2

11. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +3

12. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 +2 +1

13. Periodic Table of the Elements 1H1H 2 He 3 Li 4 Be 5B5B 6C6C 7N7N 8O8O 9F9F 10 Ne 11 Na 12 M g 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 M n 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104105106107108109110111112 No ions for noble gases.

14. Combining Ions Remember: Charges must add to zero. Na + with S 2- Na + S 2- Na + Na 2 S Ca 2+ and Cl -1 Cl -1 Ca 2+ Cl -1 CaCl 2 +1 -2 +2 +1

15. Combining Ions Remember: Charges must add to zero. Mg +2 with S 2- Mg +2 S 2- MgS Al 3+ and Br -1 +2 -2 +3 AlBr 3 Br -1 Al 3+

16. Combining Ions Remember: Charges must add to zero. Mg +2 with N 3- Mg +2 N 3- Mg +2 N 3- Mg +2 Mg 3 N 2 +2 -3 +2

17. You Do One… Remember: Charges must add to zero. Ba +2 with I - I - Ba +2 I - BaI 2 +2

18. And another… Remember: Charges must add to zero. Al 3+ with F - AlF 3 +3

19. Again… Remember: Charges must add to zero. Al 3+ with O 2- Al 2 O 3 +3-2 +3

20. Transition-metal Cations Named with positive charge as Roman numeral +1 = (I) +2 = (II) +3 = (III) Only rarely are charges bigger than three.

21. Transition-metal Cations Several elements can, under different conditions, form ions with different charges. Iron is +2 or +3, Iron(II) or Iron(III) Copper is +1 or +2, Copper(I) or Copper(II) A given ion will have only one charge; its value depends on how the ion was formed.

22. Combining Ions Rules are the same; charges add to zero. Chromium(III) with chloride Cr +3 Cl - Cl - Cl - CrCl 3 +3

23. Write these formulas… Silver oxide +1 -2 +1 Ag 2 O

24. Write these formulas… Iron(III) iodide +3 FeI 3

25. Write these formulas… Copper(II) oxide +2 -2 CuO

26. Write these formulas… Copper(I) oxide +1 -2 Cu 2 O +1

27. Polyatomic Ions Multi-atom Ions Usually are negative Usually contain oxygen Names often end in -ite or -ate Charges and formulas cannot be predicted from Periodic Table

28. Polyatomic Ions Nitrate = NO 3 -1 –One N plus three oxygens; total charge = -1 Carbonate = CO 3 -2 –One carbon plus three oxygens; total charge = -2 Sulfate = SO 4 -2 –One S plus four oxygens; total charge = -2 Hypochlorite = ClO -1 –One Cl plus one oxygen; total charge = -1

29. Good News! Same rules for writing ionic formulas using ployatomic ions as for “simple ions” Charges of all ions must add to zero

30. Combining Ions Rules are the same; charges add to zero. Sodium nitrate Na +1 and NO 3 -1 NaNO 3 +1

31. Combining Ions Rules are the same; charges add to zero. Sodium carbonate Na +1 and CO 3 -2 Na 2 CO 3 +1 -2 +1

32. Combining Ions Rules are the same; charges add to zero. Magnesium nitrate Mg +2 and NO 3 -1 Mg(NO 3 ) 2 +2 Note: where more than one polyatomic ion occurs, it must be enclosed in parentheses. A subscript always follows the closed parenthesis.

33. Write these formulas… Copper(I) carbonate +1 -2 Cu 2 CO 3 +1

34. Write these formulas… Iron(II) nitrate +2 Fe(NO 3 ) 2

35. Write these formulas… Ammonium phosphate +1 -3 (NH 4 ) 3 PO 4 +1 Note, this polyatomic ion appears only once and does not have parentheses.

36. Names these substances... Na 2 SO 4 Cu 2 S FeS Fe 2 S 3 FeSO 4 Mg 3 N 2 Mg(NO 3 ) 2 Sodium sulfate Copper(I) sulfide Iron(II) sulfide Iron(III) sulfide Iron(II) sulfate Magnesium nitride Magnesium nitrate