1. BR: Combining Objects A XY2 B XY CYZ D YZ2 RECORD as notes
How many clothespins 
and how many articles 
of clothing do you see 
in A? B? C? D?
A: one pair of pants and two clothespins
B: one pair of pants and one clothespin
C: one sock and one clothespin
D: two socks and one clothespin
CYZ D
YZ2
A XY2 B XY
X = pants
Y = clothespins
Z = sock

2. Today’s Standards
H.C.3A.1
Construct explanations for the formation of molecular compounds via sharing of electrons and for the formation of ionic compounds via transfer of electrons.
H.C.3A.2 Use the periodic table to write and interpret the formulas and names of chemical compounds (including binary ionic compounds, binary covalent compounds, and straight-chain alkanes up to six carbons).
H.C.3A.3 Analyze and interpret data to predict the type of bonding (ionic or covalent) and the shape of simple compounds by using the Lewis dot structures and oxidation numbers.

3. Homework
Complete ALL work - on time!

4. Science Connection Ionic compounds affect my everyday experiences,
so I should be able to name and write formulas
for these compounds
Two types of ionic compounds
Binary/monatomic vs. polyatomic

5. Names and Formulas for Ionic Compounds
Writing formulas for ionic compounds
Oxidation numbers
(charge tells what is done with e; # tells how many e)
Metals are positive they give electrons
 Transition metals vary
Nonmetals are negative they take in electrons
 Group 13 is 3+
 Group 14 is 4 ±
 Group 15 is 5 ± and/or 3 ±
 Group 16 is 2-
 Group 17 is 1-
 Group 18 is 0
 does not have to give, take, or share e
 to get 2 or 8 electrons in outer shell! 

6. cross Criss AlF 3 Al1 F3 Names and Formulas for Ionic Compounds
Writing formulas for ionic compounds
- Criss cross method
Find the chemical formula for aluminum 
fluoride.
 Al metal in Group 13; ox. #, 3+
 fluoride is F nonmetal in Group 17;
ox. #, 1-
First is criss then there’s cross – criss cross
 Al F
cross Criss  
Al1 F3
AlF
3 3

7. cross Criss AlF 3 Al1 F3 Names and Formulas for Ionic Compounds
B1 - 11/28
Names and Formulas for
Ionic Compounds
Writing formulas for ionic compounds
- Criss cross method
Find the chemical formula for aluminum 
fluoride.
 Al metal in Group 13; ox. #, 3+
 fluoride is F nonmetal in Group 17;
ox. #, 1-
First is criss then there’s cross – criss cross
 Al F
cross Criss  
Al1 F3
AlF
3 3

8. Names for Ions and Ionic Compounds
Chemical nomenclature is a 
systematic way of naming 
compounds.
Name the cation followed by the anion.
For monatomic, cations use the element 
name.
For monatomic anions, use the root element 
name and the suffix –ide.
To distinguish between different oxidation 
states of the same element, the oxidation state 
is written in parentheses after the name of the 
cation.
When the compound contains a polyatomic 
ion, name the cation followed by the name of 
the polyatomic ion.
IUPAC
Roman Numerals
Check table

9. Names for Ions and Ionic Compounds
Ionic compounds (M, NM)
Metal followed by nonmetal; nonmetal ends in -ide
Cations in the form of transition metals
metal followed by (Roman numeral) in parentheses, 
followed by nonmetal with –ide ending.
metals tend to give e, charge is positive
 Example 1:
 sodium and chlorine
 metal, nonmetal ID the elements
 chlorine becomes chloride
 sodium chloride
 Example 2 :
 rust, Fe2O3
 iron and oxygen
 transition metal, nonmetal ID the elements
 oxygen is in group 16; wants 2 more electrons
 Iron wants to give 3 electrons
  iron (III) oxide

10. Metallic and Nonmetallic Combinations
When writing formulas for polyatomic ions,
 use parentheses to keep the best friends together
Check charge for ion’s oxidation 
number/state
Metallic ions are + cations
Nonmetallic ions are – anions
Metal and nonmetal soooooo Criss Cross!!
Example:
Ammonium sulfate
NH4 and  SO4
NH4 1+ SO4 2-   
(NH4)2SO4

12. You Try These:
Which subscripts would 
you most likely use for an 
ionic compound 
containing an alkali metal 
and a halogen? 
(Remember,
1 = no written subscript)
A. 1 and 2
B. 2 and 1
C. 2 and 3
D. 1 and 1
What is the name of the 
compound CaOH?
A. calcium oxide
B. calcium (I) oxide
C. calcium hydroxide
D. calcium peroxide

13. You Try These:
Which subscripts would 
you most likely use for an 
ionic compound 
containing an alkali metal 
and a halogen? 
(Remember,
1 = no written subscript)
A. 1 and 2
B. 2 and 1
C. 2 and 3
D. 1 and 1
What is the name of the 
compound CaOH?
A. calcium oxide
B. calcium (I) oxide
C. calcium hydroxide
D. calcium peroxide

14. You Try These: Name these LiBr MgCl2 Al(OH)3 CuSO4
Give the formula for the following
Iron (III) oxide
Lead (IV) chromate
Zinc nitrate
Potassium chloride