GCSE Chemistry Revision Notes (all the hard stuff)

Chemistry Electrolysis -Anode - + - non-metal (anions) -Cathode - - - metal (cations) -In an aqueous solution with a reactive metal (Al or G1, G2 element) hydrogen is given at the cathode instead of the metal --> in order to extract the metal solution must be molten, not dissolved -Less reactive metals can be extracted with Carbon -In an aqueous solution with a complex non-metal ion (eg SO4, NO3), O2 is given at …

…energy than the products (energy is given out as heat during the reaction). Opposite is true for an endothermic reaction. - Breaking bonds requires energy. It is endothermic. - Making bonds gives out energy. It is exothermic. Activation energy is the energy needed for a reaction to start. It is lowered with a catalyst. Fermentation (Anaerobic respiration) Glucose --> Ethanol (alcohol) + carbon dioxide C6H12O6 --> 2 C2H5OH + 2 CO2