Ionic Compounds

pHun Reactions - 10SCIE

Finn LeSueur


Naming Ionic Compounds

  • Ions can join together to form compounds.
  • They join in such a way that their charges cancel out and the resulting compound is neutral (we will practise this later).
  • To name an ionic compound:
  1. Identify the two ions that make up the compound
  2. Write the name of each ion in that same order
  3. Hint: The positive ion (metal) will always come first
  4. Hint 2: It is important to include the (II) or (III) if it is part of the ion name.


  1. \(CaCO_{3}\)
    • \(Ca^{2+}\) and \(CO_{3}^{2-}\) ions \(\rightarrow\) Calcium Carbonate
  2. \(MgSO_{4}\)
    • Magnesium Sulfate
  3. \(Fe(OH)_{2}\)
    • Iron (II) Hydroxide
  4. \(Fe(OH)_{3}\)
    • Iron (III) Hydroxide

More Whakawai

  • Collect a sheet from the front.
  • This sheet includes every variation of ionic compounds that you should see this year!
  • Answer 20 today, but you should be able to do all of them before we have a test.

Forming Ionic Compounds

When Ions Have Equal Charges

  • Some ionic formulae are easy to generate
  • This occurs when they have equal and opposite charges. E.g.
    • Potassium Chloride: \(K^{+}\) and \(Cl^{-1}\).
    • Simply remove the charges and join them together: \(KCl\).
    • Magnesium Sulfate: \(Mg^{2+} + SO_{4}^{2-} \rightarrow MgSO_{4}\)
    • Notice how the charge is removed, but we keep it \(O_{4}\)! That is because the 4 tells us how many oxygen atoms there is!

Whakawai / Practise

Make these simple ionic compounds:

  1. Hydrogen Chloride
  2. Calcium Sulfide
  3. Aluminium Phosphate
  4. Ammonium Hydrogen Carbonate
  5. Potassium Hydroxide
  6. Iron (II) Oxide
  7. Zinc Sulphate
  8. Iron (III) Nitride

Akoranga 13 Mahi Tuatahi

Form these simple ionic compounds:

  1. Copper Sulfate
  2. Sodium Nitrate
  3. Potassium Chloride
  4. Aluminium Nitride
  5. Iron (III) Phosphate

Te Whāinga Ako

  1. Be able to form complicated ions using swap-and-drop

Write the date and te whāinga ako in your book

When the Charges are Unequal

Swap and Drop!

  1. Remove the sign from the charges (+/-)
  2. Swap the numbers between the ions
  3. Drop them down to the bottom
Lithium Oxide Aluminium Hydroxide Ammonium Sulphate

Whakawai / Practise

Make these more complicated ionic compounds:

  1. Hydrogen Sulphate
  2. Lithium Oxide
  3. Calcium Carbonate
  4. Lead Phosphate
  5. Lead Nitride
  6. Lead Nitrate


  • Education Perfect on Ions and Compounds
  • Make notes in your book of any new information you find that you think you should know!