1. Day 9 Ionic Compounds with Polyatomic Ions
SCI 10 Chemistry

2. Polyatomic ions
Polyatomic ion: an ion made up of 2 or more different atoms
The charge belongs to the entire ion
There are covalent (non-ionic) bonds between the atoms
Names often end in “ate” or “ite” instead of “ide”
Check out the back of your periodic table!

3. Naming ionic compounds with polyatomic ions
FORMULA TO NaMe:
Write the name of the metal (the cation)
Write the name of the polyatomic ion
Ex: NaNO3 = sodium nitrate

4. Try It!
Name:
AlBO3
Aluminum borate
KClO3
Potassium chlorate

5. Transition metal + polyatomic ions
Don’t forget that when there is a transition metal you must indicate its charge with brackets & Roman numerals
To find the charge of the transition metal, draw it out!
Ex: Fe(OH)3
This is iron (III) hydroxide

6. Transition metal + polyatomic ion
Ex: CuSO4
Copper (II) sulfate

7. Naming ionic compounds with polyatomic ions
NaMe to FORMULa:
Formulas are written as before except:
The polyatomic ion has to be placed inside brackets and the subscript written on the outside if you need more than one
Ex: Magnesium hydroxide
Ma(OH)2

8. Examples Iron (II) sulfate Magnesium nitrate Fe SO4 2+ 2-
2+ 2-
Charges cancel (add to zero) so just rewrite the symbols: FeSO4
Magnesium nitrate
Mg NO3
2+ 1-
Mg(NO3)2

9. Try it! Find the name for: CuCO3 (NH4)2SO4 copper (II) carbonate
ammonium sulfate

10. Try it! Find the formula for: Ammonium sulfide lead (II) nitrate NH4 S
(NH4)2S
lead (II) nitrate
Pb NO3
Pb(NO3)2

11. Practice Write the formula: sodium hydroxide magnesium phosphate
lead (IV) hydroxide
aluminum sulfate
Write the name:
(NH4)2O
Na2SO4
Ca(OH)2
Ca(CO3)
Pb(CO3)

12. To do:
Day 9 Practice Ionic Compounds with Polyatomic Ions