Chemical bonding

• ionic bonding is a non-metal and a metal
• covalent bonding is between 2 non-metals
• metallic bonding is between 2 metals
• positive ions are cations
• negative ions are anions
• ionic lattices

  • giant structures
  • held together by electrostatic forces
• covalent bonds are strong because they are attracted to both nucleuses of the atom
• metals are made of giant structures of regular lattices
• metallic bonds can carry a charge
• Double and triple covalent bonds are normally stronger than single covalent bonds. And so, more energy is needed to break them.
• a limitation to the ball and stick method is that you do not see how many electrons are shared and the atoms are closer than what the diagram shows
• Solids

  • very close together
  • vibrate in a fixed position
  • fixed shape and volume
• liquids

  • close together but move randomly
  • fixed volume
  • change shape and fill a container
• gases

  • far apart
  • move randomly
  • change shape and fill container
• limitations of the "simple sphere" model

  • forces are not shown
  • shows particles as spherical
  • shows particles as a solid
• State changes

  
• strong forces between particles

  • more energy
  • high melting and boiling
• weak forces between particles

  • low energy
  • low melting and boiling
• Ionic compounds form giant ionic lattice structures, which are held together by strong electrostatic forces.
• ionic bonds

  • lots of energy needed to overcome electrostatic forces
  • high melting and boiling
  • cannot conduct when solid
• small covalent molecules

  • strong bonds
  • weak intermolecular forces
  • low melting and boiling due to forces
• polymers

  • strong covalent bonds
  • weak intermolecular forces
  • melt easily
• giant covalent structures

  • high melting and boiling due to strong bonds
  • no intermolecular forces
• pure metals

  • high melting and boiling
  • strong electrostatic forces between metal ions and delocalised electrons
  • soft and malleable due to layers
• alloys

  • mixture
  • harder than pure metals
  • layers are distorted
• diamond

  • does not conduct
  • bonded to 4 carbon atoms
  • high melting points
  • hard
• graphite

  • conducts
  • bonded to 3 carbons
  • soft as layers can slide
• graphene

  • single layer of graphite
  • very light
  • very strong bonds
  • can be used in electronics
• buckminsterfullerene

  • C60
  • catalysts
  • lubricants
  • medical uses
• carbon nanotubes

  • strong covalent bonds
  • used in electronics
  • nanotechnology
  • strengthening materials