Types of Covalent Strucrures

• Covalent bonds need a lot of energy to break atoms
• Simple molecular substances

  • To melt or boil only need to break the weak intermolecular forces and not the strong covalent bonds
  • Low melting and boiling points
  • The more molecular forces a molecule has the stronger the attraction and the harder it is to break the intermolecular forces
  • Do not conduct electricity (no free electrons or charge)
• Giant covalent structures

  • Huge numbers of non-metal atoms
  • Regular repeating lattices
  • Diamond, Graphite, Silocon Dioxide
  • Very strong
  • High melting and boiling points as you have to break the strong covalent bonds
  • Don't conduct electricity even when molten, apart from graphite
• Silicon Dioxide

  • Silicon and Oxygen atoms in a ratio of 1:2
  • Also known as silica
  • Main component of sand