Polyatomic Compounds

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Polyatomic Compounds
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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!!!!
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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.
• Write the name of the metal
• (including the roman numeral if
  necessary)
• 2. 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
• __________________

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Polyatomic Exception

• There is only one really common positive
  
• polyatomic ion,
• This polyatomic will form ionic compounds with
  non metals.
• To name these compounds,
• _________________
• _________________

• NH4 ? _____________
• NH4Cl
• __________________
• (NH4)2O
• __________________

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Multivalent/Polyatomic Chemical Formula

• Give the chemical formula for the following
  compounds
• Maganese (II) Sulphide
• Tin (IV) Flouride
• Copper (II) Phosphate
• Ammonium Sulphate

• __________________
• __________________
• __________________
• __________________

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• 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
• 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!
• Na3PO4

Try Copper (II) Nitrate