Using Resources

Question 1

What is sustainable development

Answer 1

Development that meets the needs of the current generation without compromising the ability of future generations to meet their own needs

Question 2

In the UK, potable water is produced by

Answer 2

• Choosing an appropriate source of fresh water
• Passing the water through filter beds to remove any solids
• Sterilising to kill microbes

Question 3

What are the sterilising agents for potable water

Answer 3

• Chlorine (carefully monitor amount)
• Ultraviolet or ozone light kills microbes (more expensive)

Question 4

How is desalination carried out

Answer 4

Reverse osmosis, requires large amount of energy

Question 5

What is reverse osmosis

Answer 5

Sea water is pushed through a membrane
Only allows through water molecules
Needs high pressure to push water through
The high pressure requires a lot of energy

Question 6

How is wastewater produced and how is it treated

Answer 6

• Urban lifestyles and industrial processes produce large amounts of waste water that require treatment
• Sewage and agricultural waste water require removal of organic matter
• Industrial waste water may require removal of harmful chemicals

Question 7

What are the processes involved in sewage treatment

Answer 7

• Screening and grit removal
• Sedimentation to produce sewage sludge and effluent
• Anaerobic digestion of sewage sludge
• Aerobic biological treatment of effluent

Question 8

What do new methods of mining avoid in terms of traditional mining?

Answer 8

Avoids disadvantages of traditional mining methods of digging, moving and disposing of large amounts of rock

Question 9

What is Phytomining?

Answer 9

• Plants absorb metal compounds from the soil
• Concentrates in plant tissues
• Plants are harvested
• Burned to produce ash that contains metal compound
• Then use electrolysis to extract pure metal

Question 10

What is bioleaching?

Answer 10

Bacteria
Produces leachate solutions
That contain metal compounds

Question 11

Advantages and disadvantages of bioleaching and phytomining?

Answer 11

Methods need less energy than traditional methods and can work on low concentration ores but are slow to carry out

Question 12

Describe the stages of LCA’s

Answer 12

Assess environmental impacts of:
- Extracting and processing raw materials
- Manufacturing and packaging
- Use and operation during its lifetime
- Disposal at the end of its useful life including transport and distribution at each stage

Question 13

How do we reduce the use of resources.

Answer 13

• Reuse and recycling of materials by end users

Question 14

Advantages of recycling

Answer 14

• Less acid rain
• Metal ore reserves last longer
• Quarrying less waste landfill creates local employment

Question 15

What is corrosion and how is it prevented?

Answer 15

Destruction of materials by chemical reactions with substances in the environment, e.g. rusting
Can be prevented by applying a coating that acts as a barrier, such as greasing, painting or electroplating

Question 16

Describe the sacrificial protection

Answer 16

Some coatings are more reactive and that metal, and will corrode instead of the less reactive one

Question 17

What is Bronze and what’s its use

Answer 17

• Alloy of copper and tin
• Used for making statues and decorative objects

Question 18

What is Brass and what’s its use

Answer 18

• Alloy of copper and zinc
• Used for producing instruments, water taps and door fittings

Question 19

How are the properties of polymers determined?

Answer 19

• Depend on what monomers they are made from and the conditions under which they are made

Question 20

Describe the structures of thermosoftening and thermosetting polymers

Answer 20

Thermosetting do not melt on heating, polymers are linked by strong cross-links
Thermosoftening soften easily on hearing and then can be remoulded, keeping new shape on cooling, polymer molecules are attracted to each other by weak IM forces

Question 21

How is glass made

Answer 21

• Most of the glass we use soda-lime glass, made by heating a mixture of sand, limestone and sodium carbonate

Question 22

How are clay ceramics made

Answer 22

Shaping wet clay and heating in a furnace

Question 23

How are composites formed

Answer 23

Fibres or fragments of one material are surrounded by a binder/matrix material that holds these fibres/fibres together

Question 24

Key points of the Haber process

Answer 24

• Purified H2 and N2 gasses are passed over Fe catalyst at 450°C and 200atm
• Fe speeds up rate of reaction, so a lower temp can be used
• Some of the hydrogen and nitrogen form to make ammonia
• The reaction is reversible so ammonia breaks down again into nitrogen and hydrogen
• On cooling, ammonia liquefies and is removed, remaining hydrogen and nitrogen are recycled
• Ammonia is used for production of fertilisers

Question 25

Why is Haber process at such a high temp and pressure?

Answer 25

Conditions are a compromise between rate and the yield:
- Reaction is exothermic, lower temp would give higher yield but would be too slow
- Higher pressure gives a higher yield, but would be too expensive because of the cost of energy to produce the high pressure

Question 26

How are compounds of nitrogen, phosphorus and potassium used?

Answer 26

To make NPK fertilisers to improve agricultural productivity

Question 27

How is the phosphate rock utilised in the production of fertilisers

Answer 27

-React with nitric acid to produce phosphoric acid and calcium nitrate
- react with sulfuric acid to produce a mixture of calcium phosphate and calcium sulfate
- Phosphate rock can be reacted with phosphoric acid to produce calcium phosphate