Chemistry paper one

• C2- In Group one, the reactivity increases as you go down the group in group 7, It decreases actually go down the group
• C3- comparing graphite and diamond
• C6- electrolysis of molten ionic compounds

  When a simple ionic compound (e.g bromine lead) is electrolysed in the molten state using electrodes, The metal is produced at the cathode and the non-metal at the Anode. this is because the metal is the positive ion, and the non-metal is the negative ions.
• C6- using electrolysis to extract metals

  Metals with a high boiling point like aluminium oxide are too expensive to melt so cryolite is added instead.
• C6- using electrolysis to extract metals

  The positive electrodes need to be continuously replaced, because oxygen is formed, which reacts with the carbon of the positive electrodes, forming carbon dioxide and the gradually burn away
• C6- Electrolysis of aqueous solutions


  The ions discharged when an aqueous solution is electrolysed using electrodes, depends on the relative reactivity of the elements involved
• C6- electrolysis of aqeous solutions

  at the cathode, hydrogen is produced if it’s in the water, unless the metal is LESS reactive than the hydrogen. this because the reactive ions want to stay within the solution
• C6 - electrolysis of aqeous solutions

  At The positive electrode if OH minus and halide ions (Cl minus, Br minus,) are present, then one of the halide ions will be produced. If there is no halide present, oxygen is formed. this happens because in the aqeous solution water molecules breakdown producing H plus ions and OH minus ions that are discharged