1. Classifying Binary Compounds
Binary ionic compounds contain a metal and a nonmetal.
Type I and II
Compounds containing two nonmetals
Type III
Compounds containing H and a nonmetal = Acids 4

2. Metal Cations Type I Type II
Metals that can only have one possible charge
Charge determined by position on the Periodic Table (group 1A: +1; group 2A: +2)
Type II
Metals that can have more than one possible charge (transition metals)
Metal cation’s charge (usually +1, +2, +3, or +4) determined from the charge on anion 6

3. The Modern Periodic Table

4. Type I Binary Ionic Compounds
Contain Metal Cation from Groups 1A, 2A or Al, Ga, & In (metals with only one possible ionic charge) + Nonmetal Anion
Metal listed first in formula & name
Name metal cation first, name nonmetal anion second
Nonmetal anion named by changing the ending on the nonmetal name to –ide 7

5. Name the following Type I Compounds:
You must know the simple cations and anions in Table 5.1
MgCl2
K2O
CaBr2
BaS

6. Type II Binary Ionic Compounds
Metal cation name is the metal name followed by a Roman numeral in parentheses to indicate its charge
Determine charge from anion charge
Common Type II cations in Table 5.2
Nonmetal anion named by changing the ending on the nonmetal name to -ide

7. Determining the Charge on a Cation – Au2S3
Determine the charge on the anion
Au2S3: the anion is S, since it is in Group 6A, and its charge is –2
Determine the total negative charge
Since there are 3 S in the formula, the total negative charge is –6
Determine the total positive charge
Since the total negative charge is -6, the total positive charge is +6
Divide by the number of cations
Since there are 2 Au in the formula & the total positive charge is +6, each Au has a +3 charge 9

8. Name the following Type II compounds:
CrCl3
CrCl2
Cu2O
CuO
Fe2S3

9. Type III - Binary Compounds of Two Nonmetals
Name first element in formula first. Use the full name of the element.
Name the second element in the formula as if it were an anion.
However, remember these compounds do not contain ions!
Use a prefix in front of each name to indicate the number of atoms.
Never use the prefix mono- on the first element. 10

10. mono- (not used on first nonmetal)
Prefixes
octa- 8
hepta- 7
hexa- 6
penta- 5
tetra- 4
tri- 3
di- 2
mono- (not used on first nonmetal) 1
Prefix
Subscript
Drop last “a” in the prefix if the name begins with vowel: N2O5 dinitrogen pentoxide (not pentaoxide) 11

11. Name the following Type III compounds:
CCl4
N2O3
PCl3
PCl5 CO

12. Roadmap for Naming Binary Compounds

13. Classify and name the following binary compounds:
OCl2
CaBr2
CuS
B2O3

14. Compounds Containing Polyatomic Ions
Polyatomic ions are charged entities that contain more than one atom (e.g. HSO4-)
Must memorize name, formula, and charge
Table 5.4
Polyatomic compounds contain one or more polyatomic ions.
To name these compounds you must learn to recognize the polyatomic ions.
(NH4C2H3O2) ammonium acetate 12

15. Compounds Containing Polyatomic Ions (cont.)
Name polyatomic compounds by naming cation and anion.
Non-polyatomic ions named like Type I and II
Na2SO4 sodium sulfate
Polyatomic acids contain H+ and a polyatomic anion.

16. Names of Common Polyatomic Ions

17. Oxyanions -ate ion -ate ion plus 1 O  same charge, per- prefix
chlorate = ClO3-
-ate ion plus 1 O  same charge, per- prefix
perchlorate = ClO4-
-ate ion minus 1 O  same charge, -ite suffix
chlorite = ClO2-
-ate ion minus 2 O  same charge, hypo- prefix, -ite suffix
hypochlorite = ClO- 14

18. Patterns for Polyatomic Ions
Elements in the same column on the periodic table form similar polyatomic ions.
Same number of O’s and same charge
ClO3- = chlorate  BrO3- = bromate
If the polyatomic ion starts with H, add hydrogen- before the ion’s name and add one to the charge.
CO32- = carbonate  HCO3- = hydrogen carbonate 13

19. Name the following compounds:
Na3PO4
FeCO3
(NH4)2CO3
Ca(CN)2

20. Naming Acids Formulas always begin with H as first element
Can be thought of as consisting of H+ cation and anion
Binary acids have H+ cation and a nonmetal anion
Oxyacids have H+ cation and a polyatomic anion 15

21. Naming Acids (cont)
If the anion does not contain oxygen, use the prefix hydro- plus the suffix –ic attached to the root name of the element followed by the word acid.
HBr:
When the anion contains oxygen, use the root name of the central element of the anion, with a suffix –ic or –ous, followed by the word acid. When the anion name ends in -ate, the suffix –ic is used. When it ends in –ite, the suffix –ous is used.
H2SO4:
H2SO3:
HNO3:
HNO2:

22. Naming Acids (Summary)

23. Writing Formulas from Names
For Type I, Type II, polyatomic compounds and acids:
Determine the ions present.
Determine the charges on the cation and anion.
Balance the charges to get the subscripts.
For Type III compounds, use the prefixes to determine the subscripts. 16

24. Write the formula for each of the following compounds:
diboron trioxide
copper(III) bromide
chromium (II) permanganate
phosphorus tribromide