Using Resources

Question 1

What do humans use resources for?

Answer 1

Warmth, shelter, food and transport.

Question 2

What does ‘sustainable development’ mean?

Answer 2

Meet our needs without preventing future generations from meeting theirs.

Question 3

What do we use natural resources for?

Answer 3

Food, timber, clothes and fuel.

Question 4

What do we use finite resources for?

Answer 4

Energy and materials.

Question 5

What is potable water?

Answer 5

Water that is safe to drink.

Question 6

What is the difference between potable and pure water?

Answer 6

Potable water has dissolved salts, but pure water has no dissolved salts/substances.

Question 7

How do we produce potable water in the UK? (3)

Answer 7

1) Choose a good source of fresh water.
2) Pass water through filter beds, removes leaves and suspended particles.
3) Water is sterilised to kill microbes, in the UK we use chlorine.

Question 8

What are some sterilising agents used for potable water?

Answer 8

Chlorine, ozone, ultraviolet light.

Question 9

Why is desalination used in some countries? How does desalination work?

Answer 9

It is used in some places where fresh water is scarce or too salty to drink. Desalination reduces the levels of dissolved minerals.

Question 10

How can desalination be completed? What is reverse osmosis how does it work?

Answer 10

We can use distillation to complete desalination, or we can pass the water through membranes, which is reverse osmosis?

Question 11

What are the disadvantages of desalination/reverse osmosis?

Answer 11

Expensive due to high energy levels.

Question 12

‘Plan a method to to determine the amount of dissolved solids in samples of water and their PH’

Answer 12

1. Place a small amount of our water samples and place a few drops of universal indicator, PH 7 is green.
2. Use a balance to weigh an empty evaporating basin, ensuring to record starting mass.
3. Fill evaporating basin with our water sample, around 25cm3 and place on a tripod and gauze.
4. Use a Bunsen burner to gently heat the water until it has all evaporated.
5. Let the basin cool, Weigh the cooled evaporating basin again and calculate the mass of the solids that were dissolved in the water. (Crystals would be formed)

Question 13

‘Describe a method to purify water by distillation’

Answer 13

1. Add water sample to a conical flask, place on a tripod and gauze. Attach a delivery tube to the top of a conical flask.
2. Point the delivery tube into a test tube with inside a beaker containing ice.
3. Gently heat water using a Bunsen burner to boil gently.
4. Water will evaporate and form steam.
5. Water vapour will travel through the delivery tube and enter the cold test tube.
6. Condenses back into liquid water, this is distilled water = pure water.

Question 14

Why does waste water need to be treated before releasing it into the environment?

Answer 14

Waste water contains organic molecules + harmful microorganism, as the water is used for personal hygiene etc.

Question 15

‘Describe the processes involved in sewage treatment’ (5)

Answer 15

1) Sewage is screened by passing through a mesh, to remove solids and grit.
2) Sewage settles in large Sedimentation tanks, produces a liquid effluent and sludge.
3) Sludge is taken away and digested by anaerobic bacteria - producing methane which can be used for farming/fertilisers.
4) Liquid effluent has air bubbled through it, the aerobic bacteria multiplies and the aerobic bacteria digest the microorganisms/organic molecules.
5) This can be discharged into rivers/stream.

Question 16

When is potable water easiest to produce? When is this safe to drink, what do we need to do before this?

Answer 16

If you use the ground water from aquifers - safe to drink once treated with CL, you do need to test carefully though.

Question 17

When is potable water only made salt water? What needs to happen?

Answer 17

If water is scarce, the salt water needs to be desalinated.

Question 18

Why do new methods of extracting methods need to be found?

Answer 18

Certain ores are becoming scare, like copper ores so we are extracting from low grade ores - which is harder to extract economically.

Question 19

‘Describe how phytomining is used to obtain metal compounds (4).’

Answer 19

1) Plants are grown on land containing the metal compound.
2) Plants absorb the metal compound and concentrate it in tissue.
3) Plants are harvested and burned.
4) Ash contains high concentration of metal compound

Question 20

‘Describe how bioleaching can be used to obtain metal compounds’ (3)

Answer 20

1) Bacteria are mixed with low grade ores.
2) Bacteria carry out chemical reactions to produce leachate.
3) Leachate contains desired metal compound.

Question 21

How are metal compounds processed to obtain the metal? (2)

Answer 21

Copper compounds can displace the coper using iron - more reactive than copper.
Or electrolysis

Question 22

What are the four stages assessed in a LCAs?

Answer 22

Raw Materials

Manufacture

Usage

Disposal

Question 23

When assessing raw materials, what do we consider? 2 examples.

Answer 23

How obtaining the necessary materials impact the environment. Eg.
1. Using up limited resources such as ores and crude oil.
2. Damaging habitats through deforestation and mining.

Question 24

When assessing manufacturing, what do we consider? 3 examples.

Answer 24

Manufacturing processes may have an effect on the environments, for example.
1. Using up land for factories.
2. Production of waste.
3. Fossil fuels used in transport.

Question 25

When assessing the use of a product, what do we consider? 2 examples.

Answer 25

Usage of a product and how it may affect the environment, for example A desk has very little impact. A car requiring batteries will have a significant impact.

Question 26

When assessing disposal of a product, what do we consider? 2 examples.

Answer 26

1. The disposal of outdated products has an impact on the environment For example, 1. Using up space at landfill sites. 2. Whether parts of the products can be recycled.

Question 27

'Carry out a life cycle assessment for a plastic bag'

Answer 27

Raw Materials - Produced using crude oil which is a non renewable resource, harmful to habitats if an oil leak occurs. Manufacturing - Fractional distillation cracking & polymerisation, not much waste as crude oil is completely used and cheap to manufacture. Usage - Is strong, and often reused. Disposal - Transported to landfills and recycling sites, non biodegradable and litter can end up as litter.

Question 28

'Carry out a life cycle assessment for a paper bag'

Answer 28

Raw Materials - Made from wood and trees, this is a renewable resource but it destructive to habitats. Manufacturing - Uses a lot of energy due to the amount of water. Usage - Little weak, tend to tear, can be re-used but tend not to be. Disposal - Transporting to landfills and recycling sites, it is biodegradable, non toxic and can be recycled.

Question 29

What are some of the issues with LCAs?

Answer 29

- We can measure water and energy, plus some waste products. - But we cannot be certain how damaging they are. - Estimates or judgments tend to be done, which is biased. - LCAs can be biased, supported by claims and advertising.

Question 30

What are the benefits of the reduction in use, reuse and recycling of materials?

Answer 30

- economically beneficial - Recycling is fast becoming a major industry and provides employment

Question 31

Describe how a glass bottle, and plastic bottles can be recycled.

Answer 31

Glass bottles can be reused or crushed and melted to make different glass products. Plastic bottles can be recycled to make fleece jackets and carpets.

Question 32

What is corrosion?

Answer 32

Is the destruction of materials by chemical reactions with substances in the environment.

Question 33

What substances are required for iron to rust?

Answer 33

Water and Oxygen.

Question 34

'Describe investigations to show that both air and water are necessary for rusting, state the results' (4)

Answer 34

1) 3 test tubes, each with a nail. 2) Test tube 1 is distilled water open to air (WILL RUST) 3) Test tube 2 is boiled distilled water over crude oil with no air (WILL NOT RUST) 4) Test tube 3 is anhydrous calcium chloride with air (WILL NOT RUST)

Question 35

How can corrosion be prevented? Give 3 examples.

Answer 35

By using a barrier, like grease or paint. Or we coat with a metal = electroplating.

Question 36

'Explain sacrificial protection in terms of relative reactivity' (use zinc and iron)

Answer 36

Coating with a metal zinc, is galvanising the metal. Zinc is acting as a barrier, if it gets scratched it prevents corrosion a zinc is more reactive then iron. Zinc corrodes instead of iron.

Question 37

What is the metals used to make the alloy bronze, and what is a use of bronze?

Answer 37

Copper and tin, and it used for statues.

Question 38

What are the names of the metals that make the alloy brass, what is a use?

Answer 38

Copper and Zinc, and it is used for musical instruments and door handles.

Question 39

Why is gold usually used as an alloy in jewellery? What metals is gold mixed with?

Answer 39

It is too soft, so it is alloyed with silver, copper and zinc to make it harder.

Question 40

What is the unit to measure gold? How pure is 24 and 18 ?

Answer 40

We use carat, 24 carat is 100 percent pure, 18 carat is 75 percent pure.

Question 41

What are the properties of high carbon steel? What is a use?

Answer 41

Hard but brittle, it is used for cutting tools.

Question 42

What are the properties of low carbon steel? What is a use?

Answer 42

Softer, easily shaped, used for car bodies.

Question 43

What does stainless steel contain? What are the properties? What is a use?

Answer 43

Contains chromium and nickel, it is hard but resistant to corrosion, and used in cutlery.

Question 44

What is a properties of the aluminium alloy? what is a use?

Answer 44

Low density, aeroplane bodies.

Question 45

What are steel alloys of?

Answer 45

Iron, containing specific amounts of non metal carbon + other metals.

Question 46

How is most of the glass we use made?

Answer 46

It is soda lime glass, made from sand, sodium carbonate and limestone, we heat until it melts.

Question 47

How do we make borosilicate glass?

Answer 47

Melt sand and boron trioxide.

Question 48

What are the differences in properties of the two glasses?

Answer 48

Soda Lime glass - Low melting point Borosilicate glass - Higher melting point.

Question 49

How are clay ceramics made?

Answer 49

Wet clay is shaped and heated in a furnace to harden.

Question 50

What is the structure of composites?

Answer 50

They have reinforcements, these reinforcements can consist of fibres or fragments. Surrounded by a matrix or binder.

Question 51

Explain the structure in the carbon fibre composite/reinforced concrete, give properties and uses as well.

Answer 51

Carbon Fibre - Fibres of carbon and the matrix is plastic resign, strong and light, used in cars and aircraft parts. Reinforced concrete - Steel bars surrounded by concrete, strong and used for buildings.

Question 52

'Properties of polymers depend on monomer and conditions' suggest 3 conditions that could be changed.

Answer 52

1. Temperature 2. Pressure 3. Catalyst.

Question 53

What happens to thermosoftening polymers when we heat them?

Answer 53

They melt, shape when soft, go back to solid once cooled. The intermolecular forces break, melts. When cooled, the intermolecular forces re-join.

Question 54

What happens to thermosetting polymers when we heat them?

Answer 54

Nothing, they have strong crosslinks, they are not broken down by heat.

Question 55

What is the purpose of the Haber process? What are the raw materials needed? Where does this raw material come from?

Answer 55

- To produce ammonia - Nitrogen and Hydrogen - Nitrogen comes from the air, extracted. - Methane is reacted with steam to produce hydrogen.

Question 56

'Describe the conditions for the harber process'

Answer 56

- Passed over an iron catalyst, at 450 degrees and a pressure of 200 atmospheres.

Question 57

'The Harber process is reversible' how can we increase the yield knowing this information?

Answer 57

- Some of the ammonia can break back down. - We cool the ammonia to turn it into a liquid. - We can recycle the unreacted nitrogen and hydrogen back over the catalyst.

Question 58

Why is the temperature of 450 degrees a compromise for the Haber Process?

Answer 58

1) Higher temperature would favour the reverse reaction, forward reaction is exothermic. 2) If a low temperature is used, yield or products increases as equilibrium shifts to the right. 3) But the temperature is too low, that the reaction is too slow. 4) Compromise temperature used.

Question 59

Why is a pressure of 200 atmospheres used as a compromise in the haber process?

Answer 59

1) Lower pressure would favour the reverse reaction, so higher yield of products produced. 2) Higher pressure would favour the forward reaction, equilibrium would shift to the right. 3) High pressure can be dangerous and expensive, so 200 degrees is a compromise.

Question 60

How does a catalyst effect the Haber Process?

Answer 60

NO effect on equilibrium, but WILL increase rate of reaction.

Question 61

What are the elements used in NPK fertilisers?

Answer 61

Nitrogen, Phosphorus and Potassium.

Question 62

What do nitrogen in NPK fertilisers come as? How do we make this?

Answer 62

Comes as ammonium nitrate, 1. Use ammonia produced by haber. process. 2. We can use the ammonia to produce the nitric acid. 3. React the acid with more ammonia.

Question 63

Where does the potassium come from in NPK fertilisers? How is it obtained?

Answer 63

Potassium Chloride or Potassium Sulfate - Obtained by mining, used directly.

Question 64

What are the salts produced when phosphate rock is treated with. 1. Nitric Acid 2. Sulfuric Acid 3. Phosphoric Acid

Answer 64

1. Phosphoric Acid + Calcium Nitrate. 2. Calcium Phosphate and Sulphate (single superphosphate) 3. Triple superphosphate.

Question 65

'Ammonia Nitric Acid is a neutralisation reaction, describe the differences in preparations within a school lab, and industrial lab.

Answer 65

School Lab 1. Dilute solutions to make them safe. 2. Produces crystal, requiring high energy. 3. Produces small amounts, batch process. Industrial Lab 1. Ammonia as gas, nitric acid is concentrated, this is dangerous. 2. Provided by the exothermic reaction, crystals (above, step 1) 3. Continuous process, thousands can be produced easily.