C14 - Earth's reasources Flashcards
C14 - Explain the difference between pure and potable water.
Pure water: purified water from a source that has removed all impurities.
Potable water: improved drinking water that is safe to drink or to use for food preparation, without risk of health problems.
C14 - Obtaining potable water
How potable water is obtained depends on local conditions (rainfall).
If fresh water supplies are plentiful, then purifying that will get you potable water.
If freshwater resources are limited, desalination of seawater might be the only option.
C14 - Purifying fresh water
Screening - mud, grit and large objects such as leaves and twigs are removed.
Aluminium sulphate and lime added - these make small particles of dirt clump together so that they sink to the bottom.
Chlorine/ozone or UV light added - these all remove harmful bacteria.
pH of the water is checked
C14 - Explain what desalination is and how it is done.
Desalination is when the salt is removed from salty water.
You can desalinate water by distilling it.
Heating, evaporating, cooling and condensing.
Requires huge amounts of energy, which is expensive.
C14 - Explain in detail how wastewater is processed before being released into the environment.
Step 1 - Water passed through grid to remove large objects and grit.
Step 2 - Solid sediments and sludge removed and stored for future treatment.
Step 3 - Harmful microorganisms removed by useful bacteria.
Step 4 - Useful bacteria recycled back into previous steps
C14 - Explain in detail why wastewater is processed before being released into the environment.
Clean, safe water is critical for plants and animals that live in water.
Untreated water can carry disease.
The quality of aquatic habitats is vital for maintaining biodiversity.
Harmful microorganisms can damage human health
C14 - Explain the uses of sewage slurry
Sewage slurry is what we are left with after waste has been treated
Sewage slurry is not wasted.
It can be used to make biogas - which can power the treatment plant and surrounding areas.
It can be burned to produce electricity.
C14 - Explain what phytomining is and how it works.
An alternative method of copper extraction.
Uses plants.
Some plants absorb copper compounds through their roots.
Plants are burned.
The ash contains the copper compounds.
C14 - Explain what bioleaching is and how it works.
An alternative method of copper extraction.
Uses bacteria.
Some bacteria absorb copper compounds.
Bacteria produce solutions called leachates which contain copper ions.
These can be extracted.
C14 - Outline the steps involved in the life cycle of a product.
Getting and using raw materials.
Making the product (and any packaging).
Distributing the product.
Using, reusing and maintaining the product.
Disposal of the product at the end of its useful life.
C14 - The importance of recycling
Reduces need to mine metal ores, preserving the little we have left
Prevents pollution problems that arise from metal extraction
Reduces habitat destruction and waste
Reduces greenhouse emissions and acid rain
