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• Giant covalent molecules


  Contain millions of covalent bonds
• Giant covalent substances are always solids at room temperature
• Diamond


  • Formed from the element carbon
  • Each carbon atom forms 4 covalent bonds to other carbon atoms
• Diamond contains millions and millions of carbon atoms joined by covalent bonds
• Diamond


  • Extremely hard substance
  • Cannot conduct electricity (because all outer electrons are in covalent bonds)
• Silicon dioxide (silica)


  • Contains silicon and oxygen atoms covalently bonded together
  • Has a very high melting and boiling point (because of the many covalent bonds that must be broken)