1. Naming and Formula Writing
Practice, practice, practice

2. Compounds Follow the Law of Definite Proportion.
Have a constant composition.
Two types: Ionic and Covalent (Molecular)

3. Chemical Formulas
Shows the kind and number of atoms in the smallest piece of a substance.
Molecular formula- number and kinds of atoms in a molecule.
CO2
C6H12O6

4. Two Types of Compounds Ionic Compounds Made of cations and anions.
Metals and nonmetals, generally
The electrons lost by the cation are gained by the anion.
The cation and anions surround each other.
Smallest piece is a FORMULA UNIT.

5. Naming Binary Ionic Compounds
Binary Compounds - 2 elements.
Ionic - a cation and an anion.
To write the names name the cation and change the suffix of the anion to -ide
Easy with Representative metals.
NaCl = Na+ Cl- = sodium chloride
MgBr2 = Mg+2 Br- = magnesium bromide

6. Naming Binary Ionic Compounds
Another step in the process comes with the transition metals.
Need to figure out their charges.
The compound must be neutral.
(+ and – charges must add up to zero)
In these cases- use the anion to determine the charge of the cation by doing some algebra

7. Naming Binary Ionic Compounds
Example: name CuO (Cu has multiple oxidation states, so we must do some algebra)
Need the charge of Cu, so look at O
O is -2, and there is one atom of O in the compound
copper must be +2 because there is only one atom of Cu, and the charges need to add to zero
Therefore, the answer is Copper (II) oxide
Name CoCl3
Cl is -1 and there are three of them = -3
Co must be +3
Therefore, Cobalt (III) chloride

8. Naming Binary Ionic Compounds
Write the name of Cu2S.
Since S is -2, the Cu2 must be +2, so each one is +1.
Therefore, copper (I) sulfide
Fe2O3
Each O is x -2 = -6
3 Fe must = +6, so each is +2.
Therefore, iron (III) oxide

9. Naming Binary Ionic Compounds
Write the names of the following
KCl
Na3N
CrN
Sc3P2
PbO
PbO2
Na2Se

10. KEY KCl potassium chloride Na3N sodium nitride
CrN chromium (III) nitride
Sc3P2 scandium phosphide
PbO lead (II) oxide
PbO2 lead (IV) oxide
Na2Se sodium selenide

11. Ternary Ionic Compounds
Will have polyatomic ions
At least three elements
name the ions
NaNO3
CaSO4
CuSO3
(NH4)2O

12. Ternary Ionic Compounds
LiCN
Fe(OH)3
(NH4)2CO3
NiPO4

13. Ternary Compound Key LiCN lithium cyanide Fe(OH)3 iron (III) hydroxide
(NH4)2CO3 ammonium carbonate
NiPO4nickel (III) phosphate

14. Writing Formulas The algebraic sum of the charges must add up to zero.
Get charges on ions.
Cations from PT or Table E
Anions from PT or Table E.
Balance the charges by adding subscript, which act as multipliers for the charges
Put polyatomics in parenthesis with a subscript if there is more than one

15. Writing Formulas the formula is CaCl2
Write the formula for calcium chloride.
Calcium is Ca+2
Chloride is Cl-1
Ca+2 Cl-1 would have a +1 charge.
Need another Cl-1
Ca+2 Cl2-1
the formula is CaCl2

16. Write the formulas for these
Lithium sulfide
tin (II) oxide
tin (IV) oxide
Magnesium fluoride
Copper (II) sulfate
Iron (III) phosphide
gallium nitrate
Iron (III) sulfide

17. Key Lithium sulfide LiS2 tin (II) oxide SnO tin (IV) oxide SnO2
Magnesium fluoride MgF2
Copper (II) sulfate CuSO4
Iron (III) phosphide FeP
gallium nitrate Ga(NO3 )3
Iron (III) sulfide Fe2S3

18. Write the formulas for these
Ammonium chloride
ammonium sulfide
barium nitrate

19. Key Ammonium chloride NH4Cl ammonium sulfide (NH4)2S
barium nitrate Ba(NO3)2

20. Things to look for
If cations have (), the number indicated by the Roman numeral is their charge.
If anions end in -ide they are probably from the periodic table (binary)
If anion ends in -ate or -ite it is polyatomic – there are exceptions on Table E. Three of them end in –ide. Can you find them?

21. Part 2: Covalent Compounds
Molecular (Covalent) compounds
Made of molecules.
Made by joining nonmetal atoms together into molecules.

22. Molecular compounds made of just nonmetals
smallest piece is a molecule
Molecular compounds name tells you the number of atoms.
Uses prefixes to tell you the number of each type of element

23. Prefixes 1 mono- 2 di- 3 tri- 4 tetra- 5 penta- 6 hexa- 7 hepta-
8 octa-

24. Prefixes
9 nona-
10 deca-
To write the name write two words

25. Prefixes Prefix name Prefix name -ide 9 nona- 10 deca-
To write the name write two words
Prefix
name
Prefix
name
-ide

26. Prefixes Prefix name Prefix name -ide 9 nona- 10 deca-
To write the name write two words
One exception is we don’t write mono- if there is only one of the first element.
Prefix
name
Prefix
name
-ide

27. Prefixes Prefix name Prefix name -ide 9 nona- 10 deca-
To write the name write two words
One exception is we don’t write mono- if there is only one of the first element.
Be careful with double vowels- listen to the word when deciding whether or not to use it
Prefix
name
Prefix
name
-ide

28. Name These
N2O
NO2
Cl2O7
CBr4
CO2

29. Key N2O dinitrogen monoxide NO2 nitrogen dioxide
Cl2O7 dichlorine heptoxide
CBr4 carbon tetrabromide
CO2 carbon dioxide

30. Write formulas for these
diphosphorus pentoxide
tetraiodine nonoxide
sulfur hexaflouride
nitrogen trioxide
Carbon tetrahydride
phosphorus trifluoride
aluminum chloride

31. Key diphosphorus pentoxide P2O5 tetraiodide nonoxide I4O9
sulfur hexaflouride SF6
nitrogen trioxide NO3
Carbon tetrahydride CH4
phosphorus trifluoride PF3

32. Summary: Ionic Molecular Smallest piece Formula Unit Molecule
Types of elements
Metal and Nonmetal
Nonmetals
Solid, liquid or gas
State
solid
Melting Point
High >300ºC
Low <300ºC