Topic C2

• Formations of ions:

  Ions are made when electrons are transferred

  • When metals form ions, they loose electrons to form positive ions (cations)
  • when non-metals form ions they gain electrons to form negative ions (anions)
• Ionic Bonding

  • Transfer of electrons
  • non-metal reacting with a Metal
  • metal gives electron to non - metal Creating a negative ion
• Ionic compound Structure:

  1. ionic compounds are in a giant ionic lattice
  2. The ions form a regular lattice arrangement and there are Strong electrostatic forces of attraction
• Ionic compound properties :

  1. high melting and boiling points due to their Strong bonds
  2. can only conduct electricity when Melted or dissolved in water as this is the only time the ions are free to move
• Covalent Bonding:

  1. When non-metals bond together
  2. strong bonds
  3. only electrons in outer shells are Shared
• How to draw Covalent bonds:

  • Dot and cross diagrams.

  These show the electrons by drawing them in the overlap between the outer shells of the atons

  • Displayed formula

  This shows the covalent bonds by lines between letters of the atoms. Its good for large molecules
• solids:

  • strong forces of attraction holding them close together forming a very regular lattice arrangement
  • the particles don't move from their positions so keep a definite shape
  • Vibrate about the positions
• liquids:

  • weak force ot attraction between the particles
  • randomly arranged and are free to move past eachother
  • definite volume, no definite shape
  • particles Constantly moving randomly
• Gases:

  • very weak force of attraction, particles free to move
  • move in straight lines
  • no definite shape or volume