C10-Using Resources

• What are some purposes for which humans use natural resources?

  Fuel, clothing, shelter, food, transport
• What can replace certain natural resources like rubber?

  Agricultural or synthetic products
• What are renewable resources?

  Resources that reform at a similar rate
• What is a Life Cycle Assessment (LCA)?

  An assessment of environmental impact
• What are the stages of a Life Cycle Assessment (LCA)?

  1. Raw Materials
  2. Manufacturing and Packaging
  3. Using the Product
  4. Product Disposal
• What is the raw material for plastic bags?

  Crude oil
• What is the raw material for paper bags?

  Timber
• What is a key issue with measuring some factors in LCAs?

  Some factors are hard to measure
• What is selective LCA?

  LCA with removed information for bias
• What are three ways to improve sustainability?

  1. Reducing new materials used
  2. Reusing products
  3. Recycling non-reusable products
• How does recycling reduce the need for finite resources?

  It reduces extraction energy and waste
• What is sustainable development?

  • Meeting present needs
  • Not damaging future generations
• What happens to waste metal during recycling?

  It is melted down and recast
• How is waste glass processed for recycling?

  Separated by color and composition
• What is potable water?

  Water that is safe to drink
• What are the sources and treatments for different types of water?

  • Ground water: Filtered and sterilised
  • Salt water: Desalinated
  • Waste water: Requires extensive treatment
• What is the first step in treating ground water?

  Mesh to remove large debris
• What is the purpose of sand and gravel filtration?

  To remove smaller solid bits
• What methods are used for disinfection of water?

  Chlorine gas, ozone, or UV light
• What are the two methods of desalination?

  1. Distillation
  2. Reverse osmosis
• What is the process of distillation in desalination?

  Boiling water to separate from salts
• What is reverse osmosis?

  Passing water through a selective membrane
• What are the steps in treating waste water?

  1. Screening
  2. Sedimentation
  3. Aerobic digestion
  4. Anaerobic digestion