You might consider doing the chapter acids, bases and salts .. learn solubility and insolubility of specific compounds .. LEARN the chemical tests for anions and cations as well as gasses .. chromatography .. have some ideas for 'rate of reaction', 'measuring rate', 'types of reactions' 'endothermic/exothermic' .. also know basic apparatus used in a laboratory .. sadly i havnt solved many paper 6 s in chemistry .. i dont hav much idea about them tho .. =\