chemistry 2

• what are ions? 


  charged particles
• what are atoms with a full outer shell?


  more stable
• how do metals form ions?

  losing electrons
• how do non metals form ions?

  gaining electrons
• what is ionic bonding?

  when a metal and non metal react together they lose and gain electrons and become strongly attached by electrostatic bonds
• how are ionic bonds represented?

  dot and cross diagram
• what are ionic compounds?

  compounds of ionic bonds held together in a giant ionic lattice
• what are the properties of an ionic compound?

  high melting and boiling points due to the many bonds

  solids can’t conduct electricity
• what is covalent bonding?

  atoms share electrons with eachother so that they they have a full outer shell
• how can we draw the covalent bonds?

  dot a cross

  displayed formula

  3d model
• what is a polymer?

  a large molecule made up of repeating subunits called monomers.
• what bonds are in a polymer?

  strong covalent bonds
• how do u find the molecular formula of a polymer?

  write the repeating unit in brackets and an n outside
• what is an allotrope?


  a different structural form of the same element in the same physical state
• what are the four allotropes of carbon?

  diamond

  graphite

  graphene

  fullerenes
• diamond:


  giant covalent structure

  really hard

  carbon atoms in four bonds
• graphite:


  sheets of hexagons

  there aren’t covalent bonds between the layers meaning they are free to move so it is soft and slippery

  there are within the layers and they are hard to break
• what is graphite ideal for? 


  lubrication
• graphene:


  sheet of carbon atoms joined by hexagons

  one atom thick

  very strong
• fullerenes:


  shaped like long tubes

  structures around another atom

  huge surface area
• what are fullerenes ideal for?

  delivering drugs to the bodu
• what is metallic bonding? 


  the attraction between metal ions and delocalised electrons in a metal
• what is an alloy?

  A mixture of two or more metals.