Using the earths resources.

• Why do humans use human resources?

  1. warmth.
  2. Shelter.
  3. Food.
  4. Transport
• How are many resources produced?

  Agriculture.
• Where does natural rubber come from?

  The sap of a tree.
• How is synthetic rubber produced?

  By using crude oil.
• What do scientists call water that is safe to drink?

  Potable water.
• Potable water is not the same as pure water.
• Pure water contains no dissolved substances at all.
• Potable water contains small amounts of dissolved substances.
• What provides most of the UKs potable water?

  Rain water.
• Where does rainwater collect in?

  1. Acquifers.
  2. Lakes.
  3. Rivers.
• How do we produce potable water?

  1. Choose a good source of fresh water.
  2. Pass water through filter beds removing leaves and suspended particles.
  3. Water is then sterilised to kill microbes.
• How is water sterilised in the UK?

  By using chlorine.
• Sea water has very high levels of dissolved minerals
• How is potable water produced from sea water?

  Desalination.
• What is desanilation?


  A process which reduces the levels of dissolved minerals down to an acceptable level for potable water.
• One way to carry out desalination.


  Distillation.
• Why do humans use water?

  1. Baths.
  2. Showers.
  3. Drinking.
  4. Flushing toilets.
  5. Washing clothes.
• What does water waste contain?

  1. Organic molecules such as urine or faeces.
  2. Harmful microorganisms such as bacteria.
• Process of waste water treatment

  1. Sewage is screened by passing through a mesh to remove solids and grit.
  2. Sewage settles in large sedimentation tanks producing a liquid effulent and semi solid sludge which sinks.
  3. Sludge is digested by anaerobic bacteria.
  4. Digested sludge can be used as fertilisers for farming.
• What does liquid effulent contain?

  Large amounts of organic molecules and harmful microorganisms which need to be reduced before entering the environment.
• How are organic molecules and harmful molecules reduced before water is returned to the environment?

  1. Air is bubbled through the liquid effulent allowing aerobic bacteria to multiply.
  2. This bacteria digests the organic molecules and harmful microorganisms.
• What is the easiest way to produce potable water?

  Using ground water from aquifers which is safe to drink once treated by chlorine.
• How can acquifers be polluted?

  Fertilisers from farms.
• Where is copper used?

  Electronic equipment such as phones.
• Copper ores are running out.
• What is phytomining?

  1. A process where plants are grown on land containing the metal compound that we want.
  2. These plants absorb the metal compound and concentrate in their plant tissue.
• What is bioleaching?


  Bioleaching is a process that uses microorganisms to extract metals from ores.
• In phytomining and bioleaching the metal compound is extracted from the low grade ore.
• Key points about phytomining and bioleaching.

  1. Allow us to economically extract metal from low grade ores as the earths resources are limited.
  2. Do not involve digging.
• How are raw materials often obtained?

  1. Quarrying.
  2. Mining.
• How is quarrying harmful to the environment?

  Produces large amounts of dust and destroys habitats.
• How is mining harmful to the environment?

  Can release harmful chemicals into the environment.
• It takes a lot of energy to turn raw materials into useful products.
• Why is it important that we reduce our need for raw materials?

  To save limited resources and energy and reduce the amount of waste we produce benfiting the environment.
• How can plastic bottle be recycled?


  To make fleece jackets and carpets.
• How do we recycle metals?

  We melt them and recast them into different products.
• What is corrosion?


  The destruction of materials by chemical reactions with substances in the environment.
• Examples of corrosion.

  1. Rusting.
• Rusting only applies to iron and alloys of iron such as steel.
• How to carry out experiment on conditions required for rusting?

  1. One test tube with water and air.
  2. One test tube with water but no air as it is sealed with oil.
  3. One test tube has air but no water.
  4. Leave these for several days to identify changes.