Metallic Bonding

  • Each Metal atom will lose its valence electrons to form a lattice of positive metal ions in a "sea" of delocalised electrons.Eg:Sodium
  • Metallic Bond is the strong electrostatic attraction between the positively charged cation and the negatively charged "sea" of electrons
  • Metal atoms are arranged in a giant metallic lattice.Even though metallic bonds are strong,they are not rigid.When force is applied the layers of atoms can slide over one another.This gives the metals their malleability and ductile.
  • external image i46_metallic.jpghttp://alevelnotes.com/content_images/i46_metallic.jpg
  • Presence of mobile delocalised electrons which can flow under applied potential difference makes metal a good electrical conductor in solid and molten state.
  • Metals are good heat conductors as the atoms are closely packed.Heat energy can easily be transferred from one atom to another by vibrations as well as collisions of mobile electrons.
  • Generally,metals have high mp/bp(EXCEPT Group 1) as a lot of energy is required to overcome the strong electrostatic attraction between the positively charged metal ion and the negatively charged "sea of electrons"in the giant metallic lattice.
  • When the number of valence electrons increases,the charge of the positive metal ions increases and the number of mobile electrons increases.Thus the metallic bonds becomes stronger. EG:Na which has only one valence electron has a lower mp/bp as compared to Mg which has two valence electrons.
  • http://www.drkstreet.com/resources/metallic-bonding-animation.swf <----------------------------Animation which shows the metallic bonding at work.