earth’s resources

• What is the definition of finite resources?


  Limited supply that will eventually run out
• What is the definition of renewable resources?

  Replaced or used at the same rate
• What does sustainability refer to?

  Meeting today's needs without compromising future generations
• What is a synthetic product?

  A man-made alternative product
• What is the estimated depletion year for coal if used at current rates?

  Coal will run out by 2137
• What happens if coal use accelerates?

  It will run out by 2057
• What is the estimated depletion year for tungsten at current levels?

  Tungsten will run out by 2059
• What is pure water?

  100% water with nothing else added
• What is potable water?

  Safe to drink but contains mineral ions
• What are the steps to make water safe to drink?

  1. Screen for twigs/leaves
  2. Settle sand and soil
  3. Add aluminium sulphate and lime
  4. Filter remaining particles
  5. Add chlorine to kill bacteria
  6. Check/correct pH level
• What is desalination?

  Removes salt to make water drinkable
• What is reverse osmosis?

  Water moves from concentrated to dilute solution
• What are the stages of sewage treatment?

  1. Screening
  2. Primary treatment
  3. Secondary treatment
  4. Final treatment
• What happens during primary sewage treatment?

  Solid sediments settle out and are removed
• What is the role of bacteria in secondary sewage treatment?

  They feed on remaining organic matter
• What is the purpose of final sewage treatment?

  To ensure water is safe for rivers
• What is the process of distillation?

  Heating a solution to condense it back to liquid
• What is the main disadvantage of reverse osmosis?

  It requires lots of energy
• What are the sources of wastewater?

  • Human waste
  • Household waste
  • Agricultural waste
  • Industrial waste
• What is a life cycle assessment (LCA)?

  • Assesses environmental impact
  • Covers raw materials, manufacture, distribution, use, disposal
• What factors are considered in the raw materials stage of LCA?

  Renewability, location, and transport distance
• What is assessed during the manufacture stage of LCA?

  Processes needed and potential for reuse
• What environmental impacts are considered in the distribution stage of LCA?

  Transport distance and environmental effects
• What is assessed during the product use stage of LCA?

  Environmental impact and lifespan
• What factors are considered in the disposal stage of LCA?

  Recyclability, biodegradability, and disposal method
• What methods can prevent rusting?

  • Paint/plastic
  • Oil/grease
  • Less reactive metals
• What is galvanization?

  Coating iron with zinc to prevent rust
• What are the properties of metals?

  • High density
  • Malleable and ductile
  • Hard and strong
  • Magnetic
• What are the properties of non-metals?

  • Low density
  • Brittle
  • Thermal insulators
  • Not malleable or ductile
• What is the structure of a metal?

  • Positive metal ions
  • Sea of delocalised electrons
• What is brass made from?

  Copper and zinc
• What is bronze made from?

  Copper and tin
• What are the properties of aluminium alloys?

  • Low density
  • Lightweight
  • Strong
• What is the structure of an alloy?

  • Distorted layers
  • Harder than pure metal
• What is carbon steel made from?

  Carbon and iron
• What is stainless steel made from?

  Chromium-nickel steel
• What are the uses of stainless steel?

  • Cooking utensils
  • Cutlery
  • Chemical industry
• What are the properties of ceramics?

  Hard, brittle, solid at room temperature
• Why do ceramics have high melting points?

  Strong bonds require a lot of energy to break
• What do ceramics not react with?

  Water, acid, or alkali