Ionic Compounds

• ionic bonding

  • a structure called giant ionic lattice
  • the ions form a closely packed regular lattice arrangement and there are very strong electrostatic forces of attraction between oppositely charged ions in all directions in the lattice
• similar properties

  • They all have high boiling and melting points due to many strong bonds - it takes a lot of energy to overcome this attraction
  • when they’re solid the ions are held in place so the compounds can’t conduct electricity
  • when ionic compounds melt the ions are free to move and they’ll carry electric current
  • some dissolve in water - they separate and are all free to move in the solution so they’ll carry electric current
• formula

  • empirical formula
  • if its a dot and cross diagram count up how many atoms there are of each element
  • if you’re given a 3D diagram of the ionic lattice use it to work out what ions are in the ionic compound
  • you’ll then have to balance the charges of the ions so that the overall charge on the compound is zero