• Non-metals
• Colourless gases,they occur naturally in the air.
• Monatomic.
• They are un-reactive.
• Atoms have full shells already.
• As you go down the atoms increases in size and mass.
• As you go down density also increases.
• As you go down the boiling points increases.

An ion is a charged particle. It is charged because it has an unequal number of protons and electrons.

For example the charge on a chloride ion:

Charge on 17 protons= 17+

Charge on 18 electrons= 18-

Total charge= 1-

• Occurs between metals and non-metals.
• Involves the transfer of electrons to form ions.
• Metals normally loose elecrons to form cataions (+ve charge)
• Non-metals normally gain electrons to form anions (-ve charge)
• Cataion is attracted to the anion and  an ionic bond is formed.
• The bonds are held together by an electrostatic force.
• The ions are held together in a lattice by stong ionic bonds, forming giant structures.
• The ions are in a regular pattern, all ionic solids are crystalline.
• High boiling and melting points.
• Conducts electricity when liquid and it dissovles in water.
• Doesnt dissolve in organic solvents
  

• Hydrogen and metals form positive ions, in order to gain full shells.
• The non-metals form negative ions, and their names end in -ide.
• Elements in Group 4 and 5 do not usually form ions, because their atoms would have to gain or lose several electrons, and that takes too much energy.
• Group 0 elements do not form ions; their atoms already have full shells.

• Occurs between two non-metals.
• Both need to gain electrons in order to reach full shells.
• They share electrons with a strong force of attraction.
• Atoms can share only their outer electrons.
• Low boiling and melting points.
• Bad conductors of electricity.
• They are normally hard.
• They dissolve in organic solvents.
• They make molecules.

• Made of carbon atoms, held in a strong lattice.
• Carbon atoms form covalents bond to four others.
• Each outer atom then bonds to three more.
  
• Its very hard.
• I has a very high melting point 3550ºC
• It cant conduct electricity, any ions or free electrons to carry the charge.
• Hardest substance on Earth.

• Made of only carbon atoms, held together by weak intermolecular forces.
• The covalent bond isnt strong.
• The carbon atoms form joined hexagonal rings.
• Each carbon has a covalent bond but the layers are held by weak forces, allowing the layers to slip over.
• Graphite is soft and slippery
• Good conductor of electricity.
• The fourth electron is free to move, carrying a charge.