Using Resources

Question 1

Where do natural resources come from

Answer 1

• without human input
• they conclude anything that comes from the earth sea or air

Question 2

Risks of extracting finite resources

Answer 2

• many material are made from raw, finite resources
• people have to balance social, economic and environmental effects of extracting finite resources
• for example mini metal ores is good because it provides useful products and also provides people with jobs and brings money to the area. However, mining ores is bad for the environment as it uses loads of energy, scars the landscape and produces lots of waste that destroys habitats

Question 3

What is sustainable development

Answer 3

• a approach to development that takes account of the needs of present society while not damaging the lives of future generations

Question 4

What can we do instead of stopping using finite resources

Answer 4

• chemists can develop and adapt processes that use lower amounts of finite resources and reduce damage to the environment
• for example, chemists have developed catalysts that reduce the amount of energy required for certain industrial processes

Question 5

Bioleaching

Answer 5

• bacteria are used to convert copper compounds in the ore into soluble copper compounds, separating out the copper from the ore into soluble the process
• the leachate contains copper ions, which can be extracted by electrolysis or displacement with a more reactive metal

Question 6

Phytomining

Answer 6

• this involves growing plants in soil that contains copper
• the plants can’t use or get rid of the copper so it gradually builds up in the leaves
• the plants can be harvested, dried and burned in a furnace
• the ash contains soluble copper compounds from which copper can be extracted by electrolysis or displacement using scrap iron

Question 7

Why is recycling metals important

Answer 7

• uses less energy than mining ores extracting metals
• conserves the finite amount of each metal in the earth and cuts down on the amount of waste getting sent to landfill

Question 8

How are metals usually recycled

Answer 8

By melting and then casting them into the shape of the new product

Question 9

How does glass recycling help sustainability

Answer 9

Helps by reducing the amount of energy needed to make new glass products, and also the amount of waste created when used glass is thrown away

Question 10

Glass recycling

Answer 10

1. Glass bottles can often be reused without reshaping
2. Other forms of glass can’t be reused so they’re recycled instead. Usually the glass is separated by colour and chemical composition before being recycled

Question 11

How is glass recycled

Answer 11

• the glass is crushed and then melted to be reshaped for use in glass products such as bottles or jars
• it might also be used for different purpose such as insulating glass wool for wall insulation in homes

Question 12

4 stages of life cycle assessment

Answer 12

1. Getting raw materials
2. Manufacture and packaging
3. Using the product
4. Product disposal

Question 13

Getting raw materials in life cycle assessment

Answer 13

• extracting raw materials needed for the product can damage the local environment
• extraction can also result in pollution due to the amount of energy needed
• raw materials often needed to be processed to extract the desired materials and this often needs large amount of energy

Question 14

Manufacture and packaging of life cycle assessment

Answer 14

• manufacturing products and their packaging can use a lot of energy resources and can also cause a lot of pollution
• you also need to think about any waste products and how to dispose of them
• the chemical reactions used to make compounds from their raw materials can produce waste products
• some waste can be turned into other useful chemicals, reducing the amount that ends up polluting the environment

Question 15

Use of product in life cycle assessment

Answer 15

• the use of product can damage the environment
• how long a product is used for or how many uses it gets is also a factor
• products that need lots of energy to produce but are used for ages mean less waste in the long run

Question 16

Product disposal in life cycle assessment

Answer 16

• products are often disposed of in landfill sites. This takes up space and pollutes land and water
• energy is used to transport waste to landfill, which abuses pollutants to be released into the atmosphere
• products might be incinerated which causes air pollution

Question 17

LCA of plastic bag

Answer 17

1. Crude oil
2. The compounds needed to make the plastic are extracted from crude oil by fractional distillation, followed by cracking and then polymerisation. Waste is reduced as the other fractions of crude oil have other uses
3. Can be reused
4. Recyclable but not biodegradable and will take up space in landfill ad pollute land

Question 18

LCA of a paper bag

Answer 18

1. Timber
2. Pulped timber is processed using lots of energy. Lots of waste is made
3. Usually only used once
4. Biodegradable, non-toxic and can be recycled

Question 19

Cons of LCA

Answer 19

• the effective of some pollutants is harder to give a numerical value
• so producing an LCA is not an objective method as it takes into account the values of the person caring out the assessment. This means the LCA can be biased
• selective LCAs, which only show some of the impacts of a product on the environment can also be biased as they can be written to deliberately support the claims of a company in order to given them positive advertising

Question 20

What is potable water

Answer 20

• water thats been treated or is naturally safe for humans to drink
• its no pure as its not JUST H2O molecule

Question 21

Filtration for potable water

Answer 21

A wire mesh screens out large twigs and then gravel and sand beds filter out any other solid bits

Question 22

Sterilisation for potable water

Answer 22

The water is sterilised to kill any harmful bacteria or microbes. This can be done by bubbling chlorine gas through it by using ozone or ultraviolet light

Question 23

How is fresh water produced

Answer 23

• rainwater is a type of fresh water
• when it rains, water can either collect as surface water or as groundwater
• even though it has low levels of dissolved substances the freshwater still needs to be treated

Question 24

What is fresh water

Answer 24

Water that doesn’t have much dissolved in it

Question 25

What is surface water

Answer 25

Water in lakes rivers and reservoirs

Question 26

What is groundwater

Answer 26

Water in rocks called aquifers that trap water underground

Question 27

Test and purification of water experiment using distillation (desalination for water in hot countries)

Answer 27

1. Test ph of water using a ph meter. If the ph is too high or low, it needs to be neutralised until ph is 7
2. Set up distillation equipment
3. As water in flask heats up, it’ll evaporate and will enter the condenser as steam
4. The drop in temperature inside the condenser, due to the cold water around it will cause the steam to condense back into liquid water
5. Collect the water running out of the condenser in a beaker
6. Retest the ph of the water with a ph meter to check its natural
7. You can tell whether there were salts in your initial sample by looking to see whether there are any crystals in the round bottomed flask once the waters been distilled

Question 28

Reverse osmosis process to treat seawater

Answer 28

• the salty water is passed through a membrane that only allows water molecules to pass through
• ions and larger molecules are trapped by the membrane so separated from the water

Question 29

Why are distillation and reverse osmosis ineffective

Answer 29

• need loads of energy
• really expensive
• not practical for producing large quantities of fresh water

Question 30

Sewage treatment

Answer 30

1. Screening: removes any large bits of material as well as any grit
2. Sedimentation: goes into settlement tank. The heavier suspended solids sink to the bottom to produce sludge while the lighter effluent floats on the top
3. Aerobic digestion: air is pumped through the water to encourage aerobic bacteria to break down any organic matter including other microbes in the water
4. Anaerobic digestion: the sludge at the bottom of the settlement tank also moves to large tanks and gets broken down by bacteria
5. When the organic material is broken down it releases methane which is used as an energy source and the remaining digested waste can be used as fertiliser
6. For water containing toxic substances, additional stages of treatment may involve adding chemicals, UV radiation or using membranes

Question 31

Different sources of waste water

Answer 31

• at home
• agricultural systems
  Industrial processes

Question 32

Waste water from home

Answer 32

• when you flush the water down the drain, it goes into the sewers towards sewage treatment plans

Question 33

Waste water from agricultural systems

Answer 33

• produces lots of waste water including nutrient runoff from fields and slurry from animal farms
• it has to be treated to remove any organic matter or harmful microbes

Question 34

Waste water from industrial processes

Answer 34

• produce a lot of waste water that has to be collected and treated
• also has harmful chemicals so it has to undergo additional stages of treatment before it safe to be released back into the environment