BONDING

BONDING

1. metallic bonding

   • lattice of positive ions surrounded by delocalised electrons
   • electrostatic attraction between positive ions and delocalised ions

2. covalent bonding

   • can be represented using Lewis structures
     • show all outer electrons
   • pairs of electrons are shared by different atoms
     • electrostatic attraction between nuclei and shared pai of electrons
     • occurs when there is a small difference in electronegativity
   • in a dative covalent bond both electrons come from the same atom

3. ionic bonding

   • giant lattic structure made up of positive metal ions and negative non-metal ions
     • often soluble in water
     • insoluble in non-polar solvents
     • conduct electricity when molten or dissolved in water
     • high melting point
     • electrostatic attraction between oppositely charged ions
   • complete transfer of electrons - large difference in electronegativity
     • electronegativity
       • increases across a period
       • decreses down a group
       • F has the highest electronegativity