Electrolysis explained +ve electrode-ve electrode Cl - Cu 2+ Copper metal is formed here Bubbles of Chlorine gas are formed here The diagram below is a result of the fact that opposite charges attract. On reaching each electrode they lose or gain electrons and become Elements in their natural form

Ion Electron Half-Equations At the -ve electrode Cu 2 + ions receive two electrons and change to Cu metal.Since they gain electrons we say that they have been REDUCED.ie Reduction takes place at the –ve electrode. At the +ve electrode Cl - ions lose an electron and change to Cl atoms.We say that they have been OXIDISED. Now since chlorine is Diatomic it waits for another Ion to do the same so that it can be given off as Cl 2 molecules (gas).Oxidation takes place at the +ve electrode Cu eCu Reduction 2Cl - Cl 2 + 2e Oxidation To get the Redox or Ionic Equation we simply “ADD” the Oxidation and Reduction Equations together Cu eCu Reduction 2Cl - Cl 2 + 2e Oxidation Cu Cl - Cu +Cl 2 IONIC

Solubility The rule for SOLUBILITY is that: The rule for SOLUBILITY is that: Like dissolves Like This means that the substance you are trying to dissolve must have the same type of bonding as the liquid you are trying to dissolve it in. eg Covalent substances dissolve in covalent liquids Ionic substances dissolve in ionic liquids Note: most Ionic substances also dissolve in water

Melting Points and Boiling Points Ionic substances when solid, exist in very stable structures called Lattices which form strong Ionic bonds between positive and negative Ions. Therefore to break these up we require a lot of energy and hence the Melting Pts and Boiling Pts. are high. Ionic substances when solid, exist in very stable structures called Lattices which form strong Ionic bonds between positive and negative Ions. Therefore to break these up we require a lot of energy and hence the Melting Pts and Boiling Pts. are high. Covalent substances have weaker bonds than Ionic substances and have only very weak bonds between molecules(called Van der Waals forces).As a result not as much energy is required to break up these substances and hence Melting Pts and Boiling Pts.are low. An exception to this rule is Covalent Networks,such as, graphite and silicon dioxide who form large stable structures which are difficult to break up and therefore have high Mpts.&Bpts Covalent substances have weaker bonds than Ionic substances and have only very weak bonds between molecules(called Van der Waals forces).As a result not as much energy is required to break up these substances and hence Melting Pts and Boiling Pts.are low. An exception to this rule is Covalent Networks,such as, graphite and silicon dioxide who form large stable structures which are difficult to break up and therefore have high Mpts.&Bpts

Colour of Ions Whilst most ions are colourless, some are brightly coloured: Whilst most ions are colourless, some are brightly coloured: eg. Cu 2+ eg. Cu 2+ Ni 2+ Ni 2+ Dichromate Dichromate Permanganate Permanganate Chromate Chromate When these ions form a compound with another colourless ion then the compound will be the colour of the coloured ion.When two coloured ions join, the compound is a mixture of the two of the two colours eg.Copper Chromate is Green