topic 2

• Diamond

  • each carbon has 4 atoms
  • giant covalent
  • hard
  • high melting point
  • does not conduct electricity
• graphite

  • each carbon has 3 covalent bonds
  • layers of hexagonal rings
  • one electron from carbon is delocalised
  • conducts electricity
• fullerenes

  • carbon atoms with hollow shapes
  • hexagonal rings
  • first fullerene- buckminsterfullerene
• graphene

  • single layer of graphite
  • useful in electronics and composites
• Nanoparticles

  • particles that are between 1-100nm in size
  • large surface area to volume ratio
• uses of nanoparticles

  • medicine
  • electronics
  • catalysts
  • sun cream
• covalent bond

  • occurs between 2 non-metal atoms
• metallic bond

  • occurs between 2 metal atoms
• ionic bond

  • occurs between 1 metal and 1 non-metal atom
• Polymers

  • large molecules
  • atoms linked together by strong covalent bonds
  • strong intermolecular forces between polymers
• giant covalent structures

  • high melting points
  • atoms linked by strong covalent bonds
  • diamond, graphite and silicon dioxide are giant covalents
• Pure metals

  • too soft
  • can bend and be shaped as atoms are arranged in layers
• alloys

  • atoms are different sizes
  • layers disrupted
  • cannot bend as atoms make layers hard to slide