1. Inorganic Nomenclature
Naming Ionic Compounds
and Writing Formulas

2. Chemical Names and Formulas
In chemistry, chemical names and formulas are used interchangeably.
You must learn how to shift back forth between them, if given a name, write a formula, and visa versa.
We will start with the simplest inorganic compounds, binary salts.

3. Naming Binary Ionic Compounds
Binary ionic compounds consist of a metal cation and a non-metal anion.
The metal always comes first.
The –ide suffix is added to the end of the non-metal.
Sodium chloride Magnesium oxide
Potassium sulfide Aluminum bromide

4. Given the formula, write the name
1) MgS 2) KBr 3) Ba3N2 4) Al2O3 5) NaI 6) SrF2

5. 7) Li2S
8) RaCl2
9) CaO
10) AlP

6. Given the name, write the formula
Look up the common ionic charge for the metal and non-metal on your reference table
This is shown as “Selected Oxidation States,” in the top right hand corner of each element.
Note that non-metals often have more than one oxidation state: ignore all but the top one for now.

7. Magnesium Oxide formula
Look up oxidation states of Mg and O
Write each as an cation and anion Mg2+ O2-
Criss cross the charges, making them subscripts Mg2O2
Reduce by dividing by common
denominator, if necessary MgO

8. Oxidation numbers without lookups

9. Names  Formulas
2) lithium bromide 3) calcium nitride 4) aluminum sulfide 5) potassium iodide 6) strontium chloride

10. 7) sodium sulfide 8) radium bromide 9) magnesium sulfide 10) aluminum nitride 11) cesium sulfide 12) potassium chloride 13) strontium phosphide

11. Polyvalent Metals
Many of the d-block metals (transition metals) are polyvalent: they have more than one type of ion.
For example, iron: Fe2+ and Fe3+
There are two compounds of iron and oxygen: FeO and Fe2O3
Roman numerals are used to indicate the charge on the cation – they become iron (II) oxide and iron (III) oxide, respectively.

12. Tube Worms

13. Common Polyvalent MetalsFe Cu Sn Au Hg Pb Cr Mn Co

14. Rules for converting names to formulas
Write ionic charges for polyvalent metal next to the symbol, look up oxidation number for the non-metal (always the negative one!)
Criss-cross the charges to become subscripts; reduce to lowest common denominator (if necessary).

15. Names –> Formulas
1) iron(II) chloride 2) copper(I) sulfide 3) lead(IV) iodide 4) tin(II) fluoride 5) mercury(I) bromide 6) tin(II) oxide

16. Compounds with transition metals are often brightly colored, like FeCl3

17. 7) chromium(III) oxide 8) gold(I) iodide 9) manganese(II) nitride 10) cobalt(III) phosphide 11) iron(III) chloride 12) copper(II) sulfide 13) lead(II) bromide

18. Rules for converting formulas to names
Look up oxidation number of non-metal (always the negative one!)
Count number of negative charges, divide by subscript of the metal
Write I, II, III, etc. after the metal name, followed by the anion.

19. Formulas  Names
1) CuS 2) PbBr4 3) Pb3N2 4) Fe2O3 5) FeI2 6) Sn3P4

20. Cu2S
SnCl2
HgO
Hg2F2
CuCl2
CuBr
PbO

21. Polyatomic Ions Many ions are actually made of two or more non-metals.
Polyatomic ions have suffixes such as –ite, and –ate that you have heard throughout your lives.
Reference Table E lists the more common polyatomic ions.

23. Calcite: a ternary ionic compound
Calcite is an evaporite mineral found in dry lake beds
The chemical name for calcite is calcium carbonate, or CaCO3

24. Potassium Permanganate
What is the chemical formula?

25. K2Cr2O7
What is the name?

26. Ternary Ionic Compounds
Compounds containing polyatomic ions commonly have three or more different elements
These are called ternary ionic compounds.
You will need to learn to recognize polyatomic ions in names and formulas, and go to your reference tables to make conversions
Memorizing polyatomic names, formulas and charges is a good idea for future science majors

27. Names  Formulas 1) silver carbonate 2) potassium phosphate
2) potassium phosphate
3) aluminum hydroxide
4) sodium hydrogen carbonate
5) calcium acetate
6) potassium permanaganate
7) calcium perchlorate
8) lithium carbonate

28. Names  Formulas 9) magnesium hydrogen sulfite 10) sodium hypochlorite
10) sodium hypochlorite
11) tin(IV) chlorite
12) mercury(II) phosphate
13) tin(II) carbonate
14) mercury (I) acetate
15) lead(II) chromate
16) copper(I) sulfite
17) Tin (II) dichromate

29. Formulas  Names 1) AlPO4 2) KNO2 3) NaHCO3 4) CaCO3 5) Mg(OH)2
2) KNO2
3) NaHCO3
4) CaCO3
5) Mg(OH)2
6) Na2CrO4

30. 7) Ba(CN)2 8) K2SO4 9) NaH2PO4 10) NH4NO3 11) Sn(NO3)2 12) FePO4 13) Cu2SO4 14) Ni(C2H3O2)2 15) HgCO3

31. All Types Together!!
NaMnO4
PbSO4
AlBr3
NH4NO3
FePO4
Al2(SO4)3
KCN

32. Ammonium Nitrate: an ionic compound
This very important compound is ionic, despite not having a single metal ion!!

33. The good and bad of NH4NO3

34. 1
Chemical Name
Chemical Formula 2
Ammonium sulfide 3
Ba(OH)2 4
Potassium phosphate 5
CrCl3 6
Mercury (II) nitrate 7
Cu2CO3 8
Sodium nitrite 9
Li2CrO4

35. 10
Calcium hydrogen carbonate 11 HI 12
Lead (II) chlorite 13
HgO 14
Silver hypochlorite 15
CoSO4 16
Potassium cyanide 17
Sn3(PO4)4 18
Sodium hydroxide

36. 19
NH4MnO4 20
Iron (III) sulfide 21
FeSO3 22
Mercury (I) chloride 23
ZnCl2 24
Sodium chlorate 25
K2Cr2O7 26
Ammonium phosphate 27
NaMnO4 28
PbSO4

37. KHCO3
Hg(OH)2
Sn(HCO3)4
NaH
Fe(ClO4)3
Cu2CrO4

38. Iron (II) hydrogen sulfite
Aluminum perchlorate
Calcium chlorate
Ammonium hydroxide
Cobalt (II) iodide
Iron (III) carbonate
Iron (II) oxide
Silver sulfide

39. Potassium nitrate
Potassium nitrite
Ammonium chromate
Lead (IV) chlorite
Silver oxide
Iron (III) hydrogen carbonate
Barium hypochlorite
Copper (I) carbonate

40. Chemical Name
Chemical Formula
Metals are always stated first, by using the name of the element.
Metals first, non-metals second. Subscripts indicate the number of atoms of each element in the compounds.
Non-metals are stated second. They always end with an –ide suffix (sodium choride)
Parenthesis (often used for polyatomic ions) indicate that everything inside must be multiplied by the subscript.
Ex: Ca(NO3)2 has 2 atoms of N and 6 of O.
Metals with more than one valence are called polyvalent metals. The charge on the ion (always positive) can be found on the periodic table in the upper right corner of each element (oxidation numbers)
Polyvalent metals must be recognized! The common ones are Fe, Co, Au, Pb, Sn, Cu, Mn, Cr, and Hg. The charge on the metal can be determined from the non-metal or polyatomic ion.
Polyvalent metals are given Roman numerals to distinguish them from each other. (ex: Iron (II) and Iron (III))
Count the total number of negative charges (the charge on the ion * subscript on the ion) and divide by the number of atoms of the cation to get the charge on the cation.
Polyatomic ions are made up of combinations of non-metals, and occasionally metals.
The charges on the polyatomic ions are found on Table E.
Polyatomic ions have unique names and charges. Many of them end in –ate or –ite suffixes. Most are negative ions. They can be found on Table E (front page)
Polyatomic ions always have the same charge.
Chemical names often must be converted into formulas. Here is a simple way to do this:
Write the name of the metal, followed by the non-metal or polyatomic ion.
Write the charge of the negative ion as a superscript to the right of the symbol. For non-metals, the charge is always the top oxidation number on the periodic table. Polyatomic charges must be looked up on Table E.
Write the charge on the positive ion, given in the periodic table or in the chemical name
Criss-cross the ionic charges; the anion supersript becomes the cation subscript; the cation charge becomes the number of anions.
If necessary, reduce to lowest common denominator.
Examples:
CaCl2
chloride has –1 charge. Calcium is always +2.
Write name: calcium chloride (no II necessary)
Fe(NO3)3
NO3 is nitrate (Table E), w/ -1 charge
Fe can be II or III. Which one?
Since there are 3 nitrates, the charge on the Fe must be +3
Write the name: iron (III) nitrate.
Ex. Barium Sulfate: Ba is +2; sulfate is SO42- from table E. Criss cross leaves Ba2(SO4)2
Reduce to lowest common denomentator: BaSO4.
(NH4)2CO3 : Both of these ions are on Table E! NH4+ is ammonium; CO32- is carbonate; ammonium carbonate