Using Resources

• What is meant by a finite resource?

  An energy resource that is being used up at a faster rate that it can be replaced. These will eventually run out if we keep using them at the current rate.
• What is meant by a renewable resource?

  A resource that can be replaced at the same rate at which it is used up.
• Name 3 finite resources

  1. Metal ores to extract metals

  2. Crude oil to make polymers and petrochemicals, and to make petrol, diesel and kerosene for transport

  3. Limestone to make cement and concrete
• What are some advantages of fossil fuels which are finite resources?

  They are ready made fuels and cheap to extract.
• What are some disadvantages of fossil fuels which are finite resources?

  There is only a limited supply and they often give off atmospheric pollutants.
• Name 8 types of renewable energy resources.

  Solar, wind, tidal, wave, geothermal, hydroelectric power, biomass and wood.
• What is an advantage of renewable resources?

  They are potentially infinite energy supplies.
• What are some disadvantages of renewable resources?

  They are expensive and potentially damaging to the environment.
• What is meant by a natural material?

  A material that can be made or obtained from living things.
• What is meant by a synthetic material?

  A material that can be made from chemicals.
• Give 4 examples of natural materials?

  Cotton, paper, silk and wool.
• Give an example of a synthetic material?

  Plastic.
• Give examples of natural products that are replaced or supplemented by synthetic products (6)

  1. Cotton (clothes, textiles) - polyester

  2. Wood (construction) - PVC composites

  3. Linseed oil (paint) - acrylic resin

  4. Wool (clothes, carpets) - acrylic fibre

  5. Silk (clothes) - nylon

  6. Rubber (tyres, washers) - synthetic polymers
• What do natural resources which are supplemented by agriculture provide?

  Food, timber, clothing and fuels
• Finite resources from the Earth, oceans and atmosphere are processed to provide...

  ...energy and materials
• What do humans use the Earth's resources to provide?

  Warmth, shelter, food and transport
• Sustainable development


  Development that meets the needs of current generations without compromising the ability of future generations to meet their own needs
• Name 3 types of water purification.

  Filtration, sedimentation and chlorination.
• Explain filtration.


  Water is sprayed onto layers of sand and gravel, which filters out any insoluble solids.
• Explain sedimentation.


  A chemical is added to the water, causing tiny solid particles to clump together which, in turn, can be filtered out.
• Explain chlorination.


  Chlorine gas is injected into the water, killing any microbes.
• For humans, drinking water should have...

  ...sufficiently low levels of dissolved salts and microbes
• Potable water


  Water that is safe to drink
• Pure water


  Contains no dissolved substances - only H2O molecules (therefore potable water is not necessarily pure water)
• What do the methods used to produce potable water depend on?

  Available supplies of water and local conditions
• From where do we get water in the UK?

  Rain provides water with low levels of dissolved substances (fresh water) that collects in the ground and in lakes and rivers
• How do we produce most potable water in the UK?

  1. Choosing an appropriate source of fresh water

  2. Passing the water through filter beds (wire mesh, special filter of sand and gravel)

  3. Sterilising
• What are examples of sterilising agents for potable water?

  Chlorine, ozone or ultraviolet light
• What may be required if supplies of water are limited?

  Desalination of salty water or sea water
• How can desalination be accomplished?

  1. Distillation (boiling and condensing, sometimes under high pressure)

  2. Processes that use membranes such as reverse osmosis (semi-permeable membrane which allows water to travel through)
• These processes require...


  ...large amounts of energy so expensive
• Describe the required practical on water purification

  1. Prepare samples of sea, spring and rain water in test tubes

  2. Add universal indicator and record the colour

  3. Record the mass of a dry watch glass. Place sea water inside and warm it over a beaker full of water using a bunsen burner.

  4. Allow excess water to evaporate. Observe the dissolves solids. Measure the final mass and subtract the initial mass to find the mass of the solids.

  5. Repeat steps 1 - 4 with the other water samples and compare results.

  6. Carry out distillation of the sea water. Heat to evaporate the water. The water condenses in the condenser and you are left with pure water.

  7. Repeat steps 1 - 4 with distilled water and compare results.
• Urban lifestyles and industrial processes produce...

  ...large amounts of waste water that require treatment before being released into the environment
• What does sewage and waste water require?

  Removal of organic matter and harmful microbes
• What may industrial waste water require?

  Removal of organic matter and harmful chemicals
• Describe the sewage treatment process

  SSAA

  1. Screening and grit removal

  2. Sedimentation to produce sewage sludge and effluent (removes particles which are too small to be filtered)

  3. Anaerobic digestion of sewage sludge (to remove potentially harmful microorganisms)

  4. Aerobic biological treatment of effluent
• Comment on the relative ease of obtaining potable water from ground water

  1. Easiest way to produce potable water is to use groundwater from aquifers

  2. However may be polluted by fertilisers
• Comment on the use of sewage treatment process to produce potable water from waste water

  1. It allows us to recycle water and the sludge can be used as a fertiliser

  2. However, it has many purification steps and requires lots of energy so is only done where water is scarce
• Comment on the relative ease of obtaining potable water from salt water

  Requires a lot of energy and is expensive
• The Earth's resources of metal ores are...

  ...limited