Polyatomic Compounds Groups of atoms that can be found as parts of a molecule. These atoms bond in such a way that they have a net electric charge (usually negative) Here are some of the most common polyatomics. _____________________
You do not need to memorize these!!!!
Polyatomic Compounds We will not be drawing the structures for these atoms at this time. However, we do need to be able to name them. 1. Write the name of the metal
(including the roman numeral if necessary) Write the name of the polyatomic
Note: For a polyatomic, you do not need to change the ending of the molecule to - ide.
Name the following Ca3(PO4)2 __________________ CuSO4 __________________ BeCO3 __________________
Polyatomic Exception There is only one really common positive polyatomic ion, This polyatomic will form ionic compounds with non metals.
NH4+ ďƒ _____________
To name these compounds, 1. _________________
Multivalent/Polyatomic Chemical Formula Give the chemical formula for the following compounds Maganese (II) Sulphide
Tin (IV) Flouride
Copper (II) Phosphate Ammonium Sulphate
e.g. 1/ What is the chemical formula of sodium phosphate? Step 1 – Write the symbols of each ion, beginning with the cation (metal) Na PO4 Step 2 – Write the ionic charge above each +1 -3 Na PO4
Try: Copper (II) Nitrate
Step 3 – Cross the charge to the oppose ions subscript +1 -3 Na PO4 Step 4 – Re-write the formula. Make sure you put brackets around the polyatomic ion if it has gained a new subscript!