1. Writing Formulas and Naming Compounds

2. Binary Compounds Compounds that are made up of only 2 elements
Two types of binary compounds:
Ionic Compounds – metals and nonmetals (Ex: NaCl, MgBr2, K2O)
Covalent Compounds – 2 nonmetals (Ex: CO2, H2O, SO3)

3. Practice – Ionic or Covalent?
NO2
P2O4
Fe2O3
CaF2
covalent
covalent
ionic
ionic

4. Naming Covalent Compounds
1. Use prefixes to indicate the number of each element
mono – 1
di – 2
tri – 3
tetra – 4
penta – 5
hexa – 6 hepta – 7 octa – 8 nona – 9 deca – 10

5. Naming Covalent Compounds
2. Name the first element. If you have only one atom of the first element, do NOT use the prefix mono-. 3. Name the second element with prefixes. Change the ending to “-ide.”

6. Naming Covalent Compounds - Practice
SO3
N2O4
CCl4
5. H2O
carbon dioxide
sulfur trioxide
dinitrogen tetroxide
carbon tetrachloride
dihydrogen monoxide

7. Writing Covalent Compounds
PCl3
phosphorus trichloride
nitrogen dioxide
sulfur hexabromide
4. diphosphorus pentoxide
NO2
SBr6
P2O5

8. Naming Ionic Compounds
Name the first element (metal)
Name the second element (nonmetal) and change the ending to ”-ide”
NO PREFIXES!!!

9. Naming Ionic Compounds - Practice
NaCl
CaF2
Ag2O
AlBr3
5. ZnS
sodium chloride
calcium fluoride
silver oxide
aluminum bromide
zinc sulfide

10. Writing Ionic Formulas
Ionic compounds are composed of a positive ion called a cation and a negative ion called an anion.
Write the metal ion first ( + ion: cation)
Write the nonmetal last ( - ion: anion)
Balance the charges! Charges must add up to zero to form a neutral compound.

11. Writing Ionic Formulas
To determine the charge:
You can look at the position of the element on the periodic table to determine the charge of the element when it forms an ion
There is a difference between a neutral element (K) and an ion (K+)

12. Periodic Table Charges

13. Writing Ionic Compound Formulas
1. sodium chloride NaCl 2. calcium chloride CaCl2
Na+
Cl-
Ca+2
Cl-
Cl-

14. Writing Ionic Compound Formulas
3. aluminum chloride Al+3 Cl- AlCl3
Cl-

15. Writing Ionic Compound Formulas
4. potassium bromide K+ KBr 5. potassium oxide K2O
Br-
O-2

16. Writing Ionic Compound Formulas
6. aluminum oxide Al+3 Al2O3
O-2
O-2
O-2

17. Ionic Compounds with Roman Numerals
The roman numeral gives the charge of the metal ion.
Ex: Fe(II) Fe Fe(III) Fe+3
Transition metals need roman numerals in the name.
Pb and Sn need roman numerals because they have charges of +2 and +4.
Ag and Zn do NOT need roman numerals because Ag is always +1 and Zn is always +2.

18. Ionic Compounds with Roman Numerals – Write the Formula
nickel (II) bromide
lead (IV) oxide
3. iron (III) sulfide
NiBr2
PbO2
Fe2S3

19. Ionic Compounds with Roman Numerals – Name the Following
CrCl3
FeO
SnCl4
4. Cu2O
chromium (III) chloride
iron (II) oxide
tin (IV) chloride
copper (I) oxide

20. Review: Write the Formula
SrF2
strontium fluoride
chromium (III) oxide
sulfur hexabromide
iron (III) sulfide
carbon disulfide
Cr2O3
SBr6
Fe2S3
CS2

21. Review: Name the Following.
potassium selenide
K2Se
CaI2
NiCl2
PCl3
BaNa2
calcium iodide
nickel (II) chloride
phosphorus trichloride
banana 

22. Naming Compounds with Polyatomic Ions
Name the metal
Name the polyatomic ion
Use roman numeral if needed

23. Naming Polyatomic Ions – Practice: Name the Compound
magnesium carbonate
MgCO3
Na2SO4
Cu(OH)2
4. Zn(C2H3O2)2
sodium sulfate
copper (II) hydroxide
zinc acetate

24. Naming Polyatomic Ions – Practice: Write the Formula
Al(NO3)3
aluminum nitrate
ammonium sulfite
iron (III) chlorate
4. calcium phosphate
(NH4)2SO3
Fe(ClO3)3
Ca3(PO4)2

26. Review: Covalent compounds are made up of nonmetals only.
Use prefixes in the names of covalent compounds.
Covalent compounds do not have charges!
Ionic compounds are made up of a metal and a nonmetal.
Balance the charges when you write a formula for ionic compounds.
Never use prefixes in the names of ionic compounds!