Covalent Bonding


Covalent Bonding is split into simple covalent structures and giant covalent structures.
Simple Covalent Structures:
  • Covalent Bonding is the sharing of electrons between non-metallic elements so as to achieve the stable electronic configuration of a noble gas.
  • A covalent bond is the electrostatic attraction between the pair of negatively charged pair of shared electrons and the positively charged nuclei as a result of non-metallic atoms sharing electrons.
  • The atoms are bonded by strong covalent bonds and the molecules are then held together by weak van der Waals forces.
  • Simple Covalent Molecules generally have low mp/bp as very little energy is required to overcome the weak van der Waals forces between the molecules.
  • The degree of the intermolecular attraction is largely dependent on the size of the molecules. EG:Chlorine has stronger van der Waals forces as compared to Fluorine.
  • Larger molecules have more electrons and a greater distortion of electron cloud can be resulted.This gives rise to a stronger degree of van der Waals forces and more energy required to overcome the intermolecular attraction,thus resulting in higher mp/bp.
  • Melting/Boiling only overcomes the van der Waals forces.Covalent Bonds are NOT broken by melting/boiling.
  • Simple covalent molecules are poor electrical conductors at any states as there are no mobile ions/electrons. (Exceptions:Polar molecules which react with water to form ions,the aqueous solution conducts electricity because of the presence of mobile ions.)
  • Non-polar molecules are generally more soluble in non-polar solvents.Polar molecules are generally more soluble in polar solvents such as water.
  • Compounds with simple covalent molecules are soft because breaking of deforming the structure only requires the breaking of the weak intermolecular forces between molecules.
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