1. Naming
Ionic Compounds

2. Charges
Elements will gain or loose electrons to have 8 valence electrons. (This is the octet rule)
How many valence electrons does Na have?
If you lose that electron, what charge will you have? +1

3. Charges
Group 1A  +1
Group 2A  +2
Group 3A  +3
Group 4A  +4 / -4
Group 5A  -3
Group 6A  -2
Group 7A  -1
Group 8A  STABLE
The charges of monatomic ions, or ions containing only one atom, can be determined by referring to the periodic table

4. Ions An ion is an atom or group of atoms that has a charge
A compound that is composed of ions is called an ionic compound.
Ionic compounds usually form between a metal and a nonmetal.
They may also form between a polyatomic ion (like ammonium) and either a metal or nonmetal.
In ionic compounds, you will TRANSFER valence electrons

5. Ions A cation An anion A monatomic ion is one element with a charge
positive ion
formed when an atom loses electrons.
Example: Na+
An anion
negative ion
is formed when an atom gains electrons
Example: Cl-
A monatomic ion is one element with a charge
A polyatomic ion is more than one element with a charge
Example: SO42-

6. Formation of Ionic Compounds
Remember that objects with opposite charges attract each other.
The strong attractive force between ions of opposite charge is called an ionic bond.
Don’t forget that even though the ions have charges, the overall charge of the compound will be …
ZERO!

7. Examples of Formula Writing
Write the formula for the compound formed between sodium and chloride
Na  Na +1
Cl  Cl -1
Na+1 Cl-1 (criss-cross charges & reduce)
Na1Cl (What’s wrong here?)
Do Not write the 1’s
NaCl

8. More examples Write the formula between Mg and Br Mg  +2 Br  -1

9. More examples
Write the formula for the compound formed between Ca and S
Ca  Ca +2
S  S -2
Ca S-2
CaS

10. Polyatomic Ions
Polyatomic ions are groups of covalently bonded atoms that have a charge
For example:
SO4 -2
NO3 –1
ClO3 –1
NH4 +1

11. Polyatomic Ions
When writing formulas, you must keep the polyatomic ions grouped together
When you write a subscript next to a polyatomic ion you MUST put parentheses around the polyatomic ion first!

12. Formula writing with polyatomic Ions
Write the formula for the compound formed between sodium and nitrate
Na +1 NO3 -1 (bring down the charges)
NaNO3

13. Formula writing with polyatomic Ions
Write the formula between ammonium and sulfate
NH SO4 -2
(NH4)2 SO4

14. More examples Copper (II) and chlorine Silver and Nitrate
Magnesium and sulfite
Calcium and sulfur
Potassium and oxygen
Ammonium and phosphate
Ammonium and chlorine
CuCl2
AgNO3
MgSO3
CaS
K2O
(NH4)3PO4
NH4Cl

15. Don’t Forget!
There are some elements that form multiple charges (the ones with the roman numerals)
That roman numeral will tell you the charge!
For example: Copper (II)  Cu +2

16. Multiple Charges to Remember
Copper
Iron
Lead
Tin
Manganese
Gold
Cobalt
+1 and +2
+2 and +3
+2 and +4
+2, +4, and +7
+1 and +3

17. Naming ionic compounds
In naming ionic compounds, name the cation first, then the anion.
Monatomic cations use the element name.
Monatomic anions use the root of the element name plus the suffix -ide.
(This means 1 element with a negative charge will end in –ide).

18. Naming ionic compounds
If an element can have more than one charge, use a Roman numeral in parentheses after the element name, for example, iron(II) to indicate the Fe 2+ ion.
For polyatomic ions, use the name of the ion.

19. Examples NaCl MgSO4 K3PO4 Ca(ClO3)2 NH4NO2 Al(ClO)3 CuSO3 Fe(NO3)2
Sodium chloride
Magnesium sulfate
Potassium phosphate
Calcium chlorate
Ammonium nitrite
Aluminum hypochlorite
Copper (II) sulfite
Iron (II) nitrate

20. More examples Lead (IV) Oxide Ammonium Permanganate
Cobalt (II) chloride
Calcium sulfide
Lithium nitrate
Sodium acetate
Tin (II) chloride
PbO2
NH4MnO4
CoCl2
CaS
LiNO3
NaCH3COO
SnCl2