Ionic compounds

• Ionic Compounds


  Have a giant ionic lattice structure
• In ionic compounds, the ions are arranged in a pattern. This is called a giant ionic lattice.
• Ionic compounds


  • There are strong electrostatic forces of attraction between oppositely charged ions
  • These forces are called ionic bonds and they act in all directions
• Sodium chloride

  • Is a giant ionic lattice
  • Can be drawn in different ways
• 3D model of ionic compound

  • Shows how big the ions are compared to each other
  • Shows that the ions are ordered in a pattern
  • Only lets you see the outer layer of the compound
• Ball and stick model of ionic compound


  • Shows how the ions are arranged
  • Doesn't show how big the ions are compared to each other
  • Makes it look like there are gaps between the ions, but there aren't really
• Ionic Compounds

  • They all have high melting points and high boiling points
  • When they're solid, the ions are held in place, so the solid compounds can't conduct electricity
  • When ionic compounds melt, the ions are free to move and they can conduct electricity
  • Some ionic compounds dissolve in water, the ions can move in the solution, so they can conduct electricity
• Finding the empirical formula of an ionic compound

  1. For a dot and cross diagram, just count up and write down how many ions there are of each element

  2. For a 3D diagram, use the diagram to work out what ions are in the compound

  3. Then balance the charges of the ions so that the overall charge on the compound is zero