2.5 using resources

• What is sustainable development?

  Development meeting current and future needs
• How is potable water produced in the UK?

  By choosing a fresh water source
• What is the purpose of filter beds in potable water production?

  To remove solids from the water
• Why is sterilization important in potable water production?

  To kill harmful microbes in the water
• What are the sterilizing agents for potable water?

  Chlorine, ozone, or ultraviolet light
• Why must chlorine levels be monitored in water treatment?

  Chlorine is a toxic gas
• What is a benefit of using ultraviolet light for sterilization?

  Avoids adding chemicals to the water
• What is reverse osmosis?

  Passing seawater through a selective membrane
• What is required for reverse osmosis to work?

  High pressure to push water through
• How is desalination carried out?

  By distillation or membrane processes
• What produces large amounts of wastewater?

  Urban lifestyles and industrial processes
• What must be removed from sewage and agricultural wastewater?

  Organic matter and harmful microbes
• What may industrial wastewater require removal of?

  Organic matter and harmful chemicals
• What are the processes involved in sewage treatment?

  • Screening and grit removal
  • Sedimentation to produce sludge and effluent
  • Anaerobic digestion of sewage sludge
  • Aerobic biological treatment of effluent
• What do new mining methods avoid?

  Disadvantages of traditional mining methods
• What is phytomining?

  Using plants to absorb metal compounds
• What is bioleaching?

  Using bacteria to produce leachate solutions
• What is the main advantage of phytomining and bioleaching?

  They need less energy than traditional methods
• What is a disadvantage of phytomining and bioleaching?

  They are slow to carry out
• What are the stages of Life Cycle Assessments (LCAs)?

  • Extracting and processing raw materials
  • Manufacturing and packaging
  • Use and operation during its lifetime
  • Disposal at the end of its useful life
• How can we reduce the use of resources?

  By reducing, reusing, and recycling materials
• What are the advantages and disadvantages of recycling?

  Advantages:

  • Less acid rain
  • Longer metal ore reserves
  • Conserved energy
  • Less mining and waste
  • Creates local employment

  
  

  Disadvantages:

  • Collection problems
  • Transport costs
  • Difficult to separate materials
• What is corrosion?

  Destruction of materials by chemical reactions
• How can corrosion be prevented?

  By applying a protective coating
• What is sacrificial protection?

  Using a more reactive metal to corrode first
• How are low density and high density poly(ethene) produced?

  Using different catalysts and conditions
• How is glass made?

  By heating sand, sodium carbonate, and limestone
• How are clay ceramics made?

  By shaping wet clay and heating it
• How are composites formed?

  • Fibres or fragments of one material
  • Surrounded by a binder/matrix material
  • Example: Fibreglass (glass fibres in polymer)
• What is thermosoftening polymers?

  Polymers that can be melted and reshaped. As they are held by weak intermolecular forces which breaks easily when heated.
• What is thermosetting polymer?

  Polymers that don’t melt when heated, as they are held by string covalent bonds.
• Steps to treat potable water:

  1. Filtration through metal mesh
• Steps to treat potable water:

  1. Filter through metal mesh
  2. Filter through sand and gravel
  3. Steriles using uv light, ozone or bubble through chlorine ⛽️
• Why copper should not be disposed in landfill sites?

  Copper are expensive, toxic and limited
• What is the advantage of adding fluoride to drinking water?

  Improve dental health