NAMING COMPOUNDS
Chemical Formula
 A chemical formula is used to show the composition of
the compound.
 Ex 1: H2O – this formula shows that there are 2
hydrogen atoms and 1 oxygen atom in a single water
molecule.
 Ex 2: Al(NO2)3 – this formula shows that there is 1
aluminum atom, 3 nitrogen atoms and 6 oxygen
atoms. Notice how you multiply the subscripts
together to get the total number of atoms involved for
oxygen.
Binary Ionic Compounds
 A binary ionic compound is a compound consisting of
2 different elements, 1 metal and 1 non metal.
 For Example:
NaCl
Notice how the metal is always written first, then the
non metal
Naming Binary Ionic Compounds
 When naming a binary ionic compound, you always
want to name the metal first, then the non-metal ion,
changing the non-metal’s ending to –ide.
 Lets look at our last example again:
 NaCl
 Na would be ‘sodium’ and Cl is ‘Chlorine’, but we need
to change the ending to –ide.
 So, the name to this compound would be
‘Sodium Chlor-ide’.
Example 2 for Binary Ionic
Compounds:
Example 3 for Binary Ionic
Compounds:
Here is a list of the most common polyatomic ions:
(It is a good idea to keep this list on hand ! You can find it as a link within
the lesson)
Naming Polyatomic ions:
 When naming polyatomic ions, they have specific
names that have already been given to them, so there
is no need to change their ending.
 Lets start with a simple example:
 NaOH
 If you refer back to the list, you will see that ‘OH’ is
‘hydroxide’. So, the name of this compound would be
‘Sodium Hydroxide’. 
Example 2: Naming Polyatomic
Ions
 (NH4)2S
 To name this compound, it starts with a polyatomic
ion, so you will need to go to your list to find the name.
 You will find that (NH4) is ammonium. Then, the
non-metal is not a polyatomic ion, so we will have to
change the ending to –ide.
 So, the final name of this compound is
‘Ammonium Sulfide’. 
Lets Reverse the Process!!
 Since you can now NAME the compounds, lets try to
give the compound based on the name!
 For Example:
 Calcium Sulfate
 We know that ‘Calcium’ is represented by Ca. We will
need to look back at our chart to see what ‘sulfate’
is….SO4^-2
 Since Ca has a charge of +2 and SO4 has a charge of -2,
our final product will be:
 CaSO4
Reverse It One More Time!
 Example 2:
 Aluminum Nitrate
 We know that aluminum is ‘Al’, but again, we must
look at our chart for ‘Nitrate’.
 Nitrate is represented as – NO3 with a -1 charge.
 Since Aluminum has a charge of +3, the formula will
be:
 Al(NO3)3
What If The Element Has More Than 1
Possible Charge! Yikes!! 
 We know all the charges for the elements in groups 1-2 and
groups 13-17, but what about those transition metals?
 Lets look at an example of how this could happen…
Example 2:
Switchin’ It Up!
 CrF3
 Since Cr is a transition metal, we do not know what charge
it has, so what do we need to do to find this out.
 We must work backwards. We know the charge of Fluorine
is -1 since it is in group 17.
 It took 3 ‘-1’ charges to bond with Cr. So, we must find out
what the charge of Chromium is to make the overall charge
zero.
 (1 x ?) + (3 x -1) = 0
 This means that each Chromium ion has a charge of +3.
 So, the name of this compound would be
Chromium (III) Fluoride
Example 2:
 PbSO4
 Pb- lead- is our transition metal and SO4 is our
polyatomic ion.
 Lets refer back to our polyatomic ion sheet to see
what the name and charge of SO4 is….
 Sulfate with a charge of -2
 It too 1 (-2) sulfate atom to neutralize a single lead
atom.
 (1 x ?) + (1 x -2) = 0
 Lead has a charge then of (+2), so this compound
is Lead (II) Sulfate
Naming Binary Covalent
Compounds:
Here Is The List Of Prefixes:
(Again, this is another list to keep on hand )
Lets Try A Few!! 
 Ex 1: N2O – Dinitrogen Monoxide
 Ex 2: SO3 – Sulfur Trioxide
 Now, you try the rest….
 Ex 3: NO –
 Ex 4: CF4 –
 Ex 5: P2O5 –
 Ex 6: N2O3 -
OXYACIDS
 These are compounds that include hydrogen, oxygen
and a third element.
 Many of the polyatomic atoms from our chart are
produced by the loss of hydrogen ions from oxyacids.
That is why the name of the polyatomic ion is used in
the name of the oxyacid as well. 
 If the poly atomic ions name ends in ‘-ate’, then change
the ending to ‘-ic’ and name the oxyacid.
 Do not put ‘hydro’ at the beginning of the name for
any oxyacid, as this is only done in binary acids, which
we will look at next.
 If the polyatomic name ends in ‘-ite’, change it to ‘-ous’.
Examples: (‘-ate’ to ‘-ic’)
 Example 1:
HNO3 – Nitric Acid
 Example 2:
H3PO4 – Phosphoric Acid
 Example 3:
H2CO3 – Carbonic Acid
Examples: (‘-ite’ to ‘-ous’)
 Example 1:
HNO2 – Nitrous Acid
 Example 2:
H2SO3 – Sulfurous Acid
(Almost Finished!) 
Naming Binary Acids
 Binary acids consist of hydrogen and a non metal,
other than oxygen.
 Here is the general format to name a binary acid:
Lets Practice:
 HF – Hydrofluoric Acid
 HI – Hydroiodic Acid
 Now, you try some….
 HCl –
 HBr –
 H2S –