Topic 10

• What do we need and where does it come from?

  • Oxygen
  • Water
  • Food
  • Clothes
  • Shelter
  • Warmth
  • Electricity
  • Fuels for transport
  • Medicines
  • Fertilisers
  • Metals
  • Plastic
  • Air
  • Rain (seawater and freshwater)
  • Plants and animals
  • Plants, animals, crude oil
  • Building materials such as limestone
• Burning fuels


  1. From oil

  2. Alternative sources
• Obtaining fuels for transport

  Burning fuels from crude oil
• Obtaining medicines and fertilisers

  From crude oil or plants
• Obtaining air and rain

  Plant / animal waste, air
• Obtaining metals


  Ores in the earth's crust
• Obtaining plastic


  Chemicals from crude oil
• Sustainable development


  Using resources to meet the needs of today without preventing people in the future from meeting their needs
• Reducing use of resources

  1. Reuse

  2. Recycle - involves product being melted down and then the material being remoulded into a new product
• Life Cycle Assessment (LCA)


  An assessment of the impact of a product on the environment throughout its life
• Factors considered in LCA

  • Use of and sustainability of raw materials (including packaging)
  • Use of energy at all stages
  • Use of water at all stages
  • Production of and disposal of waste products
  • Transportation and distribution
• Types of water

  • Pure water
  • Potable water
  • Fresh water
  • Ground water
  • Sea water
  • Waste water

  
• Potable water


  Water that is safe to drink, containing low levels of dissolved solids and microbes
• Treating potable water in the UK

  1. Filter to remove solids

  2. Sterilisation to kill microbes

  
• Obtaining potable water from seawater

  Desalination - Distillation or Reverse osmosis

  
• Treating waste water


  1. Screening and grit removal

  2. Sedimentation

  3. Aerobic treatment

  4. Anaerobic treatment of sludge

  
• Gold alloys


  • Measure of purity is carats
  • 21 carat gold is 87.5% pure gold
• Types of steel


  • High carbon steel
  • Low carbon steel
  • Stainless steel
• Methods to prevent corrosion


  • Surface coating
  • Sacrificial protection
• Extracting copper from low-grade ores

  1. Phytomining

  2. Bioleaching

  3. Leaching
• Obtaining copper from solutions

  1. Electrolysis

  2. Displacement reaction using scrap iron/steel
• Other materials


  • Polymers (thermosoftening and thermosetting)
  • Glass
  • Clay ceramics
  • Composites
• Haber process


  • Used to produce ammonia
  • Reactants are nitrogen and hydrogen
  • Reaction is reversible

  
• Conditions used in industry for the Haber process are: Temperature, Pressure, Catalyst
• Making NPK fertilisers


  1. Contain nitrogen, phosphorus and potassium compounds

  2. Ammonium nitrate is a common ingredient

  3. Potassium salts and calcium phosphate are other sources