Polyatomic Ions Quiz

Polyatomic Ions

• Polyatomic ions are groups of atoms that carry a charge.
• The charge of a polyatomic ion is determined by the number of electrons lost or gained by the atoms in the group.

Common Polyatomic Ions

• The most common polyatomic ions are those containing oxygen and a nonmetal atom.
• The names of these ions follow a predictable pattern, with the suffix "-ate" or "-ite" being used to indicate the number of oxygen atoms.
• "Per-ate" ions have one more oxygen atom than the "ate" ion.
• "Hypo-ite" ions have two fewer oxygen atoms than the "ate" ion.

Sulfate and Sulfite

• "Sulfate" is the most common form of the SO4 ions.
• "Sulfite" is the form of SO4 ions with one fewer oxygen.

Phosphate and Phosphite

• "Phosphate" is the most common form of the PO4 ions.
• "Phosphite" is the form of PO4 ions with one fewer oxygen.

Other Polyatomic Ions

• "Permanganate" is MnO4-1
• "Acetate" is C2H3O2-1
• "Hydrogen carbonate" (also known as "bicarbonate") is HCO3-1
• "Dichromate" is Cr2O72-
• "Hydroxide" is OH-1
• "Cyanide" is CN-1
• "Ammonium" is NH4+1

Memorizing Polyatomic Ions

• There are helpful resources available to help memorize polyatomic ions.

Polyatomic Ions

• Polyatomic ions are groups of atoms that act as a single charged unit.
• Polyatomic ions are common in chemistry and have specific names and formulas.
• The names of polyatomic ions are often based on their chemical composition, with prefixes and suffixes indicating the number of oxygen atoms present.
• "Per-ate" ions have one more oxygen atom than "ate" ions.
• "Ite" ions have one less oxygen atom than "ate" ions.
• "Hypo-ite" ions have two less oxygen atoms than "ate" ions.
• The most common form of a polyatomic ion is typically the "ate" form.
• Common examples of polyatomic ions include:
  • Nitrate (NO3-1)
  • Carbonate (CO32-)
  • Phosphate (PO43-)
  • Sulfate (SO42-)
  • Ammonium (NH4+1)
  • Hydroxide (OH-1)
  • Cyanide (CN-1)
  • Acetate (C2H3O2-1)
  • Permanganate (MnO4-1)
  • Dichromate (Cr2O72-)
  • Hydrogen carbonate (or bicarbonate) (HCO3-1)
• The charge of a polyatomic ion can be indicated before or after the number, as long as the sign is included.
• For polyatomic ions with a charge of +1 or -1, the number 1 can be omitted, but the sign must still be present.