AQA • GCSE

Metals Elements which form positive ions Non-metals Elements which do not form positive ions Metals position on periodic table on the left hand side Non-metals position on periodic table

Metal An element that forms positive ions pH of metal oxide Basic Non-metal Does not form positive ions pH of non-metal oxide Acidic Reduction in terms of oxygen Loss of oxygen Oxidation in terms of oxygen Gain of oxygen Oxidation in terms of electrons Loss of electrons

H - Hydrogen He - Helium Fe - Iron N - Nitrogen Na - Sodium F - Fluorine Li - Lithium C - Carbon CO2 - carbon dioxide

Requirements for a reaction to take place Particles must collide, with sufficient energy Activation energy Minimum amount of energy required to start a chemical reaction Reaction profile diagram A graph which shows the change in energy of a chemical reaction Products The new substances formed by a chemical change

Mixture A combination of two or more substances that are not chemically joined. Filtration Separates insoluble solids from liquids. Crystallisation The formation of crystals by cooling a saturated solution Simple distillation Used to separate a liquid from a solution

Transition elements are found In the middle block of the periodic tableRe Physical properties of transition elements Hard, high melthing points, strong and dense. Chemical properties of transition elements Slow/no reaction with oxygen, water and halogens Charges on transition metal ions Form positive ions often with the ability to form more than one ion

Ion An atom or group of atoms that has lost or gained electrons and therefore a positive or negative charge. Polyatomic ion An ion that is made of more then one atom Metal ion an atom which has lost electrons forming a positive ion Non-metal ion an atom which has gained electrons forming negative ions. Covalent bond a shared pair of electrons Molecule two or more atoms held together by covalent bonds Metallic bonding Positively charged metal ions are surrounded by delocalised outer ...

Evaluate how far the power of the executive has been undermined by constitutional reforms since 1997 PARA 1 - P1 - P1 - devolution Blair, as part of his democratising reforms, enabled referendums to be held on devolving legislative powers to Scotland, Wales and NI. This has undermined the power of the executive by granting other assemblies powers that used to be held at westminster. Westminster now has no say on certain areas of legislation in devolved assemblies. 1997 resulted in an overwh...