The Earth’s Resources Flashcards
Examples of finite resources
Fossil fuels, limestone
Examples of renewable resources
Solar, wood chips
What is potable water?
Water that is fit to drink
How is water treated?
- Water is filtered of large objects
- Water is sent to settlement tank and sand settles out
- Aluminium sulphate and lime are added
- Water is filtered again to get rid of any other finer particles
- A small amount of chlorine or ozone is added to kill remaining bacteria
- pH of water is checked and corrected
- Water is stored in tanks before being piped off
What is sewage?
Waste water
How is sewage treated?
- Screening ~ large objects and grit are removed
- Primary Treatment ~ water is rotated in large circular tank to removed sludge
- Secondary Treatment ~ microorganisms in the water are killed by useful bacteria
- Final Treatment ~ useful bacteria settles out and waste water is safe to be put in rivers and sea
How can sludge be used?
Digested anaerobically by microorganisms and biogas is produced
What can biogas be used for?
To power sewage treatment plants, provide electricity, to produce methane gas
How do you analyse a sample of water?
- Pour 1cm depth of water sample 1 into a test tube and add a few drops of universal indicator
- Match the colour with a colour on the pH colour chart and record the results
- Repeat for water samples 2 and 3
- Weigh a dry watch glass and record its mass
- Pour 4cm cubed of water sample 1 into the watch glass and place it about beaker acting as a water bath
- Allow all water to evaporate from watch glass but don’t let the water bath boil dry
- Remove watch glass with tongs and allow it to cool
- Reweigh the watch glass and work out mass of dissolved solids
- Repeat steps 5-8 for water samples 2 and 3
How do you purify a sample of water by distillation?
- Place the water sample in a conical flask and set up the apparatus for distillation
- Heat the water using a bunsen burner until it boils
- Reduce the heat so the water boils gently
- The distilled water will collect in the cooled test tube
- Collect 1cm depth of distilled water and then stop heating
- Analyse the distilled water with cobalt chlorine paper
What are the two methods of extracting copper from copper-rich ores?
Sulphuric acid and smelting
How is sulphuric acid used to extract copper from copper-rich ores?
It creates copper sulphate solution before extracting the copper metal
How is smelting used to extract copper from copper-rich ores?
Copper is heated to a high temperature in a furnace with air to produce impure copper
How is copper extracting through phytomining?
Plants that have absorbed copper ions are burnt and copper is extracted from the ash
How is copper extracting through bioleaching?
Bacteria feed on low grade copper ores
What does LCA stand for?
Life Cycle Assessment
Why are LCAs carried out?
To assess the impact of getting/processing raw materials, making packaging and products, maintaining/using/reusing the product and disposing of the product on the environment
How is an LCA carried out?
Listing all energy and material inputs and outputs
Evaluating potential environmental impacts from inputs and outputs
Interpreting the results to make decisions
What are the stages of a life cycle of a product?
- Raw material
- Manufacture
- Reuse
- Recycling or Waste Management
What is Reduce, Reuse, Recycle?
A message seen in green campaigns
What are the aims of RRR campaigns?
Use of energy and limited resources, and waste we produce
How is aluminium extracted through electrolysis?
Extracted from molten aluminium oxide at high temperatures
Why is recycling better than electrolysis?
Saves energy and money
How do you recycle aluminium?
- Scrap aluminium
- Feed conveyer
- Shredder
- Deviated
- Melting furnace
- Filtration unit
- Chin casting unit
- Shredder
- Ingots
