c3 - structure and bonding

• delocalised

  the free movement of ions
• intramolecular and intermolecular forces

  
• cation

  • positively charged ion
  • formed by losing electrons
• anion

  • negatively charged ion
  • formed by gaining electrons
• ion

  • formed when an atom has lost or gained one or more electrons
  • are attracted to other ions with the opposite charge, due to electrostatic forces
  • atoms become a positive ion (metals) when it loses electrons and a negative ion (non metals) when it gains electrons
• atoms

  • one way atoms achieve a full outer shell of electrons (to become stable) is by gaining or losing electrons
  • atoms that have to lose or gain only 1 or 2 electrons are much more likely to form ions, as it requires less energy
  • the melting and boiling point of a substance is determined by the strength of the bonds holding the atoms of that substance together
• groups and ions

  • group 1 form 1+ ions
  • group 2 form 2+ ions
  • group 6 form 2- ions
  • group 7 form 1- ions
• intramolecular forces

  • stronger than intermolecular forces, because the attraction holding compounds together are stronger than the attraction between molecules
  • occur within a molecule
• lattice

  • regular repeating arrangement of metal and non metal ions (each atom is attracted to all those around it)
  • creates compounds with very high melting points which conduct when molten or in solution but never when solid
  • examples: diamond and graphite
• transfer of electrons

  • requires a lot of energy
  • creates ions with opposite charges, that will attract each other (the force of attraction forms an ionic bond)
• ductile


  can be drawn out into wires
• malleable


  can be hammered into shape
• native metals


  • unreactive metals found in the earth’s crust as pure metals
  • examples: gold and silver
• allotrope

  • different structural forms of the same element in the same physical state
  • example: diamond and graphite are allotropes of carbon