Paper 2 (10) Flashcards
What is the purpose of a life cycle assessment (LCA)?
To assess the environmental impact of products
What the correct order for the stages of a life cycle assessment?
1) Extracting and processing the raw materials
2) Manufacturing and packaging the product
3) Using the product
4) Disposing of the product
Give two ways in which ‘extracting and processing the raw materials’ can damage the environment.
-> Cutting down trees
-> Digging of mines
-> Carbon dioxide production from energy use.
-> Release of pollutants into the environment
Life Cycle Assessments only consider the e___________ impacts, not the financial impacts.
environmental
Which of the following methods of disposal has the lowest environmental impact?
Landfill
Incineration
Recycling
Recycling
Give 2 limitations of life cycle assessments:
-> It is difficult to gather all of the required data about each step
-> Companies can manipulate their LCAs to look more favourable
-> It is difficult to compare different harms e.g. lung disease vs global warming
What is potable water?
Water that is safe to drink
What are the three criteria for water to be considered potable?
Levels of dissolved substances (e.g. salts) must be fairly low
The pH must be between 6.5 and 8.5
The must be no microorganisms
Where does the UK get most of its potable water from?
Fresh water sources
Give 2 sources of fresh water:
Lakes
Rivers
Aquifers
Surface Water vs Ground Water
Surface water is water that is exposed to the ___. It includes lakes, _______ , and reservoirs.
Ground water is water that is found under the _______, such as in_________.
Surface water is water that is exposed to the air. It includes lakes, rivers, and reservoirs.
Ground water is water that is found under the ground, such as in aquifers.
What are the benefits of relying on fresh water?
It is replaced frequently
It is easy to access
What are the three stages of treating fresh water?
1) First, pass the water through a wire mesh. This will filter out any large objects like plastic bottles or leaves.
2) Second, pass the water through a bed of sand and gravel. This will filter out smaller things like bits of rock.
3) Lastly, sterilise the water to kill any microorganisms. There are three different ways to do this: 1) bubbling chlorine gas through it, 2) exposing it to ozone, 3) exposing it to ultraviolet radiation.
What is desalination?
The extraction of potable water from sea water
What is the main drawback of using desalination to get potable water?
It requires a lot of energy, so is very expensive (and contributes to global warming)
