Chemical Bond Classification
  • Chemical bonds are classified by the way 
  the electrons are held between the 
  atoms that are bonding to each other.
    Chemical Bond Classification
  • Electrons can be held in a bond by 
   one of two ways:
   –Electrons are equally shared by both 
    atoms. (Covalent)
   –Electrons are “exchanged” from one 
    atom to another forming ions. (Ionic)
   Properties of Covalent Bonds
   • Covalent bonds occur between two 
   non-metal atoms. 
   • In covalent bonds electrons are shared 
   by the atoms involved in the bond.
            Examples of Covalent Bonds
        • Examples of compounds formed with 
           covalent bonds include:
            –Hydrogen gas (H2)
            –Ammonia (NH3)
            –Large biological molecules such as 
              glucose (C H O ).
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     Properties of Ionic Bonds
  • Ionic bonds occur between a metal 
   atom and a non-metal atom. 
  • In ionic bonds electrons are exchanged or 
   transferred from the metal atom to the 
   non-metal atom.
  • After the transfer of electrons, both atoms 
   become oppositely charged, keeping both 
   atoms together (bonded).