Polyatomic Ions Groups of Atoms with a Charge

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Polyatomic Ions - Groups of Atoms with a Charge

• CHEMISTRY

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Common Polyatomic Ions
Formulas containing polyatomic ions are similar
to formulas without them.
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Characteristics of Polyatomic Ions

• The oxidation number of a polyatomic ion is its
  Charge.
• Whenever a subscript is added to a polyatomic ion
  to make the total oxidation number in the formula
  equal zero, the ion MUST be enclosed with
  parenthesis, ( ).
• the formula for a compound composed ofCalcium
  and Hydroxide Ion is Ca(OH)2
• Parenthesis, ( ), are not used if no subscript is
  added.
• the formula for a compound composed ofCalcium
  and Carbonate Ion is CaCO3

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Write formulas for these

• Calcium Acetate
• Ammonium Phosphate
• Potassium Sulfate
• Aluminum Nitrate
• Copper (II) Chlorate
• Iron (III) Phosphate
• Barium Hydroxide
• Copper (I) Sulfite
• Mercury (III) Hydroxide
• Chromium (II) Acetate
• Tin (IV) Hydrogen Carbonate

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Answers

• Ca(C2H3O2)2
• (NH4)3PO4
• K2SO4
• Al(NO3)3
• Cu(ClO3)2
• FePO4
• Ba(OH)2
• Cu2SO3
• Hg(OH)3
• Cr(C2H3O2)2
• Sn(HCO3)4