1. POWER POINT LECTURE ON NAMING COMPOUNDS

2. There are two types of compounds that we can name:
Naming Compounds
There are two types of compounds that we can name:
-Ionic
-Molecular

3. Naming Compounds What is a chemical formula?
A representation of the # of atoms of each kind in a compound using atomic symbols and subscripts
(So there!!!)

4. Binary Ionic Compounds
Ionic compounds that contain two different atoms:
Examples: NaCl, MgF2, Li2O, AlBr3
Now let’s learn to name them!

5. Binary Ionic Compounds
The metal (or the positive component) is named 1st.
The nonmetal (or negative component) is added to the name.
Then the letters - ide are added to the ending
Example: NaCl
Na is sodium and Cl is chlorine.
Therefore NaCl is Sodium Chloride

6. Binary Ionic Compounds
Now try these: MgBr2
Mg is Magnesium and Br is Bromine.
Therefore MgBr2 is Magnesium Bromide
Li2O
Li is Lithium and O is Oxygen.
Therefore Li2O is Lithium Oxide

7. Binary Ionic Compounds
Now why is it that some formulas have subscripts?
Each atom has a different oxidation #.
This tells us in what proportions, the atoms must combine in.
For example: Mg has a +2 oxidation # and Br has a -1 oxidation #
therefore it would take 1 Mg+2 to cancel out 2 Br-1
The molecular formula is therefore MgBr2

8. Binary Ionic Compounds
Or you could look at it like this:
When you want to know what subscripts to use, simply switch the oxidation #s and turn them into subscripts.
Mg +2 Br -1 becomes
MgBr2
Get it!
Got it!
Good!

9. Binary Ionic Compounds
Now some metals have more then one oxidation state.
Examples:
Cu could be +1 or +2
Fe could be +2 or +3
Now what do we do?

10. Binary Ionic Compounds
We use the same system, but now we insert a Roman Numeral after the metal to designate the oxidation state of the metal.
Example:
For CuCl2 we would call this….
Copper (II) chloride
How do we know it was Copper (II) and not (I) ?
Remember in order to get CuCl2 we had to switch the oxidation #s, so copper must have been +2 .

11. Binary Ionic Compounds
Now you try. (You will need your Reference Table)
Name these:
Fe2O FeS CuCl
Iron (III) oxide
Iron (II) sulfide
Copper (I) chloride

12. Binary Ionic Compounds
Still a little unsure? Let’s try to explain further...
Fe2O3 was made from Fe+3 and O-2
Once we switch the oxidation #s, we get...
Fe2O Iron (III) oxide because Fe was +3.
FeS was made from Fe+2 and S-2 Once we switch the oxidation #s, we get…
FeS Iron (II) sulfide because Fe was +2.

13. Polyatomic Ionic Compounds
Naming Polyatomic ionic compounds are almost as easy as naming binary ionic compounds.
Name the positive component 1st.
Name the negative component 2nd
(No -ide ending this time)
Example: NaOH (You will need Reference Table F)
Na is Sodium and OH- (from table F) is hydroxide
therefore this compound is sodium hydroxide

14. Polyatomic Ionic Compounds
Now you try some… (and don’t let the subscripts throw you):
LiNO3 MgCO Na3PO4
lithium nitrate
magnesium carbonate
sodium phosphate

15. Polyatomic Ionic Compounds
Now you try some harder ones:
Ca3(PO4)2 (NH4)2CO Al(OH)3
calcium phosphate
ammonium carbonate
aluminum hydroxide

16. Polyatomic Ionic Compounds
What’s the deal with these subscripts again?
Each ion has a different oxidation #.
This tells us in what proportions, the atoms must combine in.
For example: Ca has a +2 oxidation # and PO4 has a -3 oxidation #
therefore it would take 3 Ca+2 to cancel out 2 PO4-3
The molecular formula is therefore Ca3(PO4)2

17. Polyatomic Ionic Compounds
Or you could look at it like this:
When you want to know what subscripts to use, simply switch the oxidation #s and turn them into subscripts.
Ca +2 PO4-3 becomes
Ca3(PO4)2
Remember!
We learned this already!
I knew you’d get it!

18. Polyatomic Ionic Compounds
I think you are ready to do some work on your own now… What do you think?
You see… this is why you are my favorite class!
Hey wait doesn’t he show this to all his classes?
Mr. Baruch - that’s not right!