Using Resources Flashcards
1
Q
What do humans use Earth’s resources for
A
- warmth
- shelter
- food
- transport
2
Q
Where do natural resources come from
A
- ocean
- Earth
- atmosphere
3
Q
What do natural resources supplemented by agriculture provide
A
- food
- timber
- clothing
- fuels
4
Q
What changes can be made to natural resources
A
Replaced by synthetic products or improved upon by man-made processes
5
Q
Example of natural resources being replaced with synthetic products
A
- rubber
- natural - extracted from tree sap
- man-made - polymers made to replace rubber
6
Q
What can provide conditions for natural resources being enhanced for our needs
A
Agriculture
7
Q
How can agriculture provide conditions for enhancing natural resources
A
Development of fertilisers meaning we can produce high crop yields
8
Q
Types of natural resources
A
- renewable
- finite/unrenewable
9
Q
Renewable resources
A
Reform at similar rate / faster than as we use them
10
Q
Example of renewable resource
A
- timber
- trees planted following harvest, only take few years to grow
11
Q
Finite resources
A
Not formed quickly enough to be considered replaceable
12
Q
Examples of finite resources
A
- fossil fuels
- nuclear fuels - uranium plutonium
- minerals/metals in ores in Earth
13
Q
What happens to minerals/metals in ores in Earth
A
- extracted
- undergo man-made processes to provide fuels/materials necessary for modern life
14
Q
Modern materials made from raw finite resources
A
Most plastics, metals and building materials
15
Q
What effects need to be considered when extracting finite resources
A
- social
- economic
- environmental
16
Q
Potable water
A
Water that’s been treated or is naturally safe for humans to drink
17
Q
Freshwater sources
A
- rivers
- lakes
18
Q
Importance of potable water
A
Essential for human life
19
Q
Is potable water pure
A
No
20
Q
Why isn’t potable water pure
A
Pure water contains only H₂O molecules, potable water contains many other dissolved substances
21
Q
Requirements of potable water
A
- pH 6.5-8.5
- low levels of dissolved salts
- no bacteria/microbes
22
Q
Fresh water
A
Water that doesn’t have much dissolved in it
23
Q
Example of fresh water
A
Rainwater
24
Q
Where is rainwater collected
A
- surface water - in lakes, rivers, estuaries
- groundwater - in rocks called aquifers that trap water underground
25
How does location affect source of fresh water
In warmer areas, surface water dries up faster, so most water comes from groundwater
26
Steps of treating water to become potable
- filtration
- sterilisation
27
Treating water - filtration
- wire mesh screens out large twigs ect.
- gravel + sand beds filter out other solid bits
28
Why is water sterilised during treatment
To kill harmful bacteria/microbes
29
How is water sterilised during treatment
- chlorine gas bubbled through it
**OR**
- ozone or UV light
30
What happens in countries where there isn't enough surface/groundwater
Sea water is treated produce potable water
31
Methods of treating seawater
- desalination by distillation
- reverse osmosis
32
Method of analysing + purifying sample of water with distillation
- test pH with pH meter
- pH too high/low - neutralise with acid/alkaline to give pH 7
- set up simple distillation aparatus
- water evaporates, rises up, condenses down condenser, into beaker as fresh water
- retest pH of water with pH meter to check it's neutral
- if salts in initial sample - crystals formed in round-bottomed flask
33
Reverse osmosis
- salt water passed through membrane that only allows water molecules to pass through
- ions + larger molecules trapped separately by membrane
34
Problems with distillation + reverse osmosis
Need much energy so are very expensive, not practical for producing large quantities of fresh water
35
Where does water go when flushed down the drain
Goes into sewers and towards sewage treatment plant
36
How do agricultural systems produce waste water
- nutrient run-off from fields
- slurry from animal farms
37
Why is sewage treated
To remove organic matter and harmful microbes to be put back into freshwater sources without polluting them or causing health risks
38
What produces waste water
- domestic processes
- agricultural systems
- industrial processes
39
How does industrial waste water treatment differ
Undergoes additional treatment stages before being safe as it can contain harmful chemicals
40
Stages of sewage treatment
- screening
- sedimentation
- aerobic digestion
- anaerobic digestion
- ADDITIONAL stages for toxic substances
41
Sewage treatment - screening
Removing large bits of material (twigs, plastic bags) as well as any grit
42
Sewage treatment - sedimentation
- stands in sedimentation tank
- heavier suspended solids sink to bottom to produce sludge
- lighter effluent floats on top
43
Sewage treatment - aerobic digestion
- effluent from sediment tank
- air pumped through water to encourage aerobic bacteria to break down organic matter, including microbes in water
- water released back into environment
44
Sewage treatment - anaerobic digestion
- sludge from sediment tank taken to large tank
- bacteria breaks down organic matter in sludge, releasing methane
- methane used as energy source
- remaining digested waste used as fertiliser
45
Sewage treatment - additional stages for toxic substances
- chemicals added to precipitate metals
- UV radiation
- use of membranes
46
Differences between desalination of salt water and waste water treatment
- waste water treatment requires more processes
- desalination requires more energy
47
What process is usually preferable in areas with not much drinking water
Waste water treatment - less energy
48
LCAs
Life Cycle Assessments
49
Purpose of carrying out LCAs
To look at environmental impact of products
50
Stages of LCAs
- getting raw material
- manufacture and packaging
- use and operation
- product disposal
51
Problems with LCAs
- easy to quantify energy, resources, waste but difficult to give effect of pollutants negative value
- not objective - can be biased
- selective LCAs only show some impacts - biased to support company
52
Plastic bag LCA - raw materials
Crude oil
53
Plastic bag LCA - manufacturing and packaging
- fractional distillation
- cracking
- polymerisation
- waste reduced as other fractions of crude oil have other uses
54
Plastic bag LCA - use and operation
- reusable
- used for other things as well as shopping - bin liners
55
Plastic bag LCA - product disposal
- recyclable
- not biodegradable
- will take up space in landfill, polluting land
56
Paper bag LCA - raw materials
Timber
57
Paper bag LCA - manufacturing and packaging
Pulped timber processed using lots of energy, making lots of waste
58
Paper bag LCA - use and operation
Usually only used once
59
Paper bag LCA - product disposal
- biodegradable
- non-toxic
- recyclable
60
Sustainable development
Approach to development that takes into account needs of present society, while not damaging lives of future generations
61
Why are finite resources unsustainable
- will run out
- extraction uses much energy, producing waste
- processing resources into useful materials can use energy made from finite resources
62
Ways of reducing use of finite resources
- using less
- develop/adapt processes that use lower amounts of finite resources, reducing environmental damage
63
Supply of copper-rich ores
Short
64
How to improve sustainability of copper
Extracting it from low-grade copper ores
65
Low-grade copper ores
Ores without much copper in
66
Ways of extracting copper from low-grade copper ores
- bioleaching
- phytomining
67
Bioleaching
- bacteria convert copper compounds in ore into soluble copper compounds, separating copper from ore
- leachate (solution produced in process) contains copper ions - can be extracted by electrolysis or displacement with scrap iron
68
Phytomining
- growing plants in soil containing copper
- plant can't use or get rid of copper, builds up in leaves
- plants harvested, dried, burned in furnace
- ash contains soluble copper compounds - copper extracted with electrolysis of displacement with scrap iron
69
Advantage of new copper extraction methods
Smaller impact on environment - avoid traditional mining method of digging, moving + disposing of large amounts of rock
70
Disadvantage of new copper extraction methods
Slower
71
Resources produced from limited raw materials
- metals
- glass
- building materials
- clay ceramics
- most plastics
72
Importance of recycling metals
- uses less energy than mining/extraction
- less environmental impacts from quarrying/mining
- conserves finite amount of each material
- cuts down on amount of waste sent to landfill
73
How are metals usually recycled
- melted
- cast into shape of new product
- amount of separation needed depends on what metal will be used for after recycling
74
Example of metal being recycled
Scrap steel added to iron from blast furnace to reduce amount of iron needing to be extracted from iron ore
75
How is glass separated before recycling
- colour
- chemical composition
76
How is glass recycled
- melted
- reshaped
77
Does glass always have to be reshaped for reuse
No
