Giant covalent structures

• If you are unsure whether a covalent structure is a giant structure or consists of small molecules, think about whether it is a solid, liquid or gas at room temperature. Giant covalent structures are solids at room temperature, covalent structures consisting of small molecules are liquids and gases. 
• • Giant covalent structures are solids with high melting points
• • They have a huge number of non-metal atoms bonded to other non-metal atoms via strong covalentbonds
• • These structures can also be called giant lattices and have a fixed ratio of atoms in the overall structure
• Examples of giant Covalent structure:

  • diamond
  • Graphite
  • Silicon dioxide
• • Diamond, graphite and silicon dioxide all have giant covalent structures 
  • Diamond and graphite are made from carbon atoms 
  • Silicon dioxide (silica) is made from silicon and oxygen atoms
• • All giant covalent structures have high melting points because:
  • There are strong covalent bonds between atoms
  • These require lots of energy to overcome 
• giant covalent structures images