CC5 Ionic Bonding

• An ion is a charged particle (+ or -).
• An atom is neutral overall so it has equal numbers of electrons (-) and protons (+).
• An ion is formed when an atom gains or loses electrons.
• When an atom (usually a metal) loses negative electrons it becomes a positively charged ion = CATION.
• When an atom (usually a non-metal) gains negative electrons it becomes a negatively charged ion = ANION.
• Ionic bonding involves:

  • TRANSFER of electrons
  • Between metals and non-metals

  Strong electrostatic attraction between oppositely charged ions.
• Positively charged= lost electrons. 

  Negatively charged= gained electrons. 
• Ionic Compounds Structure =

  • Giant lattice structure 
  • A regular cubic arrangement

  Ions are held together by strong ionic bonds between oppositely charged ions.
• Ionic compounds properties =

  • High melting and boiling points

  Ionic bonds are strong and a lot of heat is needed to break them.
• As solids, ionic compounds cannot conduct electricity because their ions are fixed and cannot move to carry charge.
• When liquid (molten or aqueous – dissolved in water), the ions can break free of the lattice and are able to move and so can carry an electric current.