1. Unit 5 Writing and Naming Compounds
Modeling Chemistry
Unit 5
Writing and Naming Compounds

2. Time FOR
A LITTLE
REVIEW

3. Metal vs. Nonmetals Metals Nonmetals Left side of the Periodic Table
Right side of the Periodic Table plus hydrogen

4. Number of electrons an atom will gain or lose to become stable
Code:
+1, +2, +3, ±4, -3, -2, -1, 0

5. IONS A charged particle Cations: positive charged ion
“+” oxidation number
Anions: negative charged ion
“—” oxidation number

6. Chemical Bond Is the force that holds atoms or ions together
Three Types
atomic
Molecular
ionic

7. Ionic Bonds Transfer of Electrons Between a metal and a nonmetal
Ex: NaCl

8. Molecular Bonds Sharing of electrons
Between a nonmetal and another nonmetal
Ex: CO2

9. ID if it is Ionic or MolecularKF
P4O10 CO
MgO
H2O
LiCl

10. Diatomic Atoms/Molecules
Atoms of the same element bonding together
AKA: Super Seven
All are Molecular Bonds F2
Cl2
Br2 I2 H2 O2 N2

11. Naming Binary Compounds
Bi—means 2
Either
Molecular: 2 nonmetals
Ionic: 1 metal and 1 nonmetal

12. Naming Ionic Binary Compounds
2 elements present
1 metal then 1 nonmetal
Steps
Write the name of the first element
Write the name of the second element
Change the ending of the second element to “—ide”
Combine together

13. End Changing Reference
Chlorine  Chloride
Oxygen  Oxide
Nitrogen  Nitride
Sulfur  Sulfide
Phosphorus  Phosphide
Bromine  Bromide
Iodine  Iodide
Fluorine  Fluoride

14. Practice Problem #1 #2
AlF3
CaO

15. Naming Molecular Binary Compounds
2 elements both being nonmetals
Steps
Name the first elements
Name the second element
Change the ending of the second element to “—ide”
Add prefixes based on the subscribe of each element
Place together

16. Note: “Mono—” is not used on the first element
Prefixes
1 = mono—
2 = di—
3 = tri—
4 = tetra—
5 = penta—
6 = hexa—
7 = hepta—
8 = octa—
9 = nona—
10 = deca—
Note: “Mono—” is not used on the first element

17. Practice Problems #3 #4 #5
PCl3
N2O5 CO

18. Polyatomic Ions
A group of atoms that acts as a single charged unit
They are Molecular Bonds
Ex:
PO4—3

19. Naming Polyatomic Compounds
3 or more elements together
Steps
Identify the Polyatomic Ion
Write the name of the first element
Write the name of the polyatomic ions
Place together
Note: Never change the ending to Polyatomic Ions

20. Practice Problems #1 #2
KNO3
Li3PO4

21. Practice Problems #3 #4
NH4OH
(NH4)2O

23. Writing Chemical Formulas
If it equals ZERO
4a. Write the symbols next to each other
Steps
Write the symbols
Write the oxidation numbers above the symbols
See if the oxidation numbers add to equal zero
If it does not equals ZERO
4b. Cross the oxidation numbers and write as subscripts on the opposite symbol
(drop the “+” and “—”)

24. Special Notes
If a two or three is being applied to a polyatomic ion, parenthesis goes around the polyatomic ion and the subscript outside of it

25. Practice Problem #1 #2
Li & F
Mg & Cl

26. Practice Problem #3 #4
Ca & SO4
Potassium Oxide

27. Practice Problem #5 #6
Mg & ClO3
Na & PO4

28. Practice Problem #7 #8
Lithium Acetate
NH4 & NO3