CHEMICAL REACTIONS

• malleable

  capable of being shaped
• ductile

  can be drawn into wires
• physical properties of metals


  hard and strong

  
  

  solid at room temp (except mercury)

  
  

  shiny when polished

  
  

  good conductors of heat and electricity

  
  

  dense

  
  

  malleable and durable
• metals + oxygen ---->

  magnesium + oxygen ----->

  metal oxide

  magnesium oxide
• metals + water ----->

  sodium + water ---->

  metal hydroxide + hydrogen

  sodium hydroxide + hydrogen
• metals + acids ----->

  copper + hydrochloric acid ----->


  salt + hydrogen

  copper chloride + hydrogen
• what is a displacement reaction

  A reaction in which a more reactive element takes the place of a less reactive element in a compound
• what is the reactivity series


  The reactivity series places metals in increasing order of reactivity
• oxidation


  Gain of oxygen
• reduction


  loss of oxygen
• oxidising agent


  A reagent that oxidises (takes electrons from) another species.
• reducing agent


  Donates electrons and becomes oxidized.
• corrosion


  The destruction of materials by chemical reactions with substances in the environment
• what is rusting


  The corrosion of iron
• what are the two substances needed for iron to rust

  air, water
• what are methods to stop a car/bike to rust

  grease, paint, electroplating, galvanising
• What is galvanising?


  Galvanising can be used to protect iron or steel objects. The object is coated in a layer of zinc, the zinc stops water and oxygen reaching the initial metal and stops corrosion
• what are ways of extracting metal


  electrolysis, reduction with carbon, and sometimes they are found naturally
• what is an alloy


  A mixture of two or more metals
• what is a typical alloy structure

  
• examples of alloys


  bronze - copper and tin

  brass - copper and zinc

  steel - iron and other elements
• What are shape memory alloys?


  alloys that can return to their original shape after being deformed