C3 structure and bonding

C3.1

  • \

C3.2

  • when two non metals join together they share electrons it forms a covalent bond
  • ionic bonds are when a metal and

video notes

  • changing state requires lots of energy, which is why the graph flattens when it is changing state (solid, gas, liquid)
  • atoms want to have a full outer shell and share or transfer electrons to become ions
  • group 1 has one electron on it’s outer shell so it needs to lose one

  -1 electron → - -1 → +1 is the charge

  • electrons cannot be made or destroyed can only be transferred or shared
  • dot and cross diagram shows the transfer of electrons so it shows ionic bonding (between metal and non-metal)
  • \

C3.3 ionic bonding

  • between a metal and non-metal
  • transfer electrons
  • shown through a dot and cross diagram
  • ions are held together by strong forces of attraction between oppositely charged ions

C3.4 giant ionic structures

  • they have high boiling points because they have strong electrostatic forces between them, it means they need a lot of energy to break
  • they can carry charge when dissolved in water or molten because ions are allowed to be mobile and flow.

C3.5 covalent bonding

  • two non metals bonding
  • share electrons
  • each shared pair of electrons is an individual covalent bond

C3.6 structure of simple molecules

  • simple structures have a lower melting and boiling point, this is because they have weak intermolecular forces (forces that hold the molecules together)
  • substances of simple molecules cannot carry electricity because they have no overall charge and can’t carry charge
  • each model has its limitations
    • electrons are shown in a fixed position when they are constantly moving
    • all electrons look identical
    • doesn’t show shape of the molecule
  • when a molecule is melted the intermolecular forces are broken
    • covalent have strong bonds but the simple molecules have weak attraction, which means a low melting/boiling point

6+