Using Resources

Question 1

How do we use the earths resources ?

Answer 1

To provide warmth, shelter, food and transport

Question 2

What are renewable vs finite resources ?

Answer 2

• Renewable energy resources are sources of power that quickly replenish themselves and can be used again (only includes wood if they are replanted)
• Finite resources have a limited supply that will eventually run out

Question 3

What is potable water ?

Answer 3

Water that is safe to drink

Question 4

Is potable water “pure” ?

Answer 4

No, it contains dissolved substances however it must have sufficiently low levels of dissolved salts and microbes

Question 5

Method to use produce potable water in the UK ?

Answer 5

• an appropriate source of fresh water is selected
• the water is passed through filter beds to remove different sized insoluble solids
• water is then sterilized to kill microbes (ozone, UV light, chlorine)

Question 6

How does desalination work and what does it do ?

Answer 6

• remove salt from water
• can be done through distillation
  Or through proceses with membranes such as reverse osmosis
• both are very expensive

Question 7

How is correct quality water produced?

Answer 7

• water is passed through a mesh screen to remove large bits
• chemicals are added to make solids and microbes stick together to form sediment and sink
• there is then anaerobic digestion of sewage sludge
• the water is then sterilized with chlorine to kill any microbes

Question 8

Is obtaining potable water from groundwater/wastewater or salt water cheaper ?

Answer 8

groundwater/wastewater

Question 9

What is phytomining ?

Answer 9

• Using plants to absorb metal compounds
• plants are harvested and then burned to produce ash that contains metal compounds

Question 10

What is bioleaching ?

Answer 10

Using bacteria to produce leachate solutions that contain metal compounds

Question 11

How can copper be obtained from solutions of copper compounds ?

Answer 11

Displacement using scrap iron
Electrolysis

Question 12

What stages are assessed when exploring environmental impact ?

Answer 12

• extracting and processing raw materials
• manufacturing and packaging
• use and operation during its lifetime
• disposal at end of useful life
• (transportation throughout stages)

Question 13

3 ways to limit use of energy sources, waste, environmental resources ?

Answer 13

• reduce
• reuse
• recycle

Question 14

Corrosion definition and example ?

Answer 14

• destruction of materials by chemical reactions with substances in the environment
• rusting (air and water necessary for iron to rust)

Question 15

How can corrosion be prevented ?

Answer 15

By applying a coating which acts as a barrier (greasing, painting, electroplating)

Question 16

How does sacrificial protection work ?

Answer 16

• more reactive metals donating electrons to any ions of the other metals that may have formed so they don’t corrode

Question 17

Alloys examples ?

Answer 17

Gold - in jewelry is usually an alloy with silver, zinc, copper (carats)
Bronze - alloy of copper and tin used in electrical connectors
Brass - alloy of copper and zinc used for tools

Question 18

How are steel alloys designed for specific uses ?

Answer 18

• low carbon steels are easily shaped, used for sheeting (malleable)
• high carbon steels are hard and used for cutting tools
• stainless steels are resistant to erosion and used for cutlery
• aluminum alloys are low density and used for aircraft

Question 19

How is soda lime glass made vs borosilicate glass ?

Answer 19

• by heating sand, sodium carbonate and limestone
• made from sand and boron trioxide, melts at higher temps

Question 20

How are clay ceramics (pottery and bricks) made ?

Answer 20

By shaping wet clay and then heating in a furnace

Question 21

Differences between low density vs high density polyethene ?

Answer 21

Low density :
- weaker forces of attraction as the chains are further apart, meaning it has a low melting point and is soft
High density :
- stronger forces of attraction as the chains are closer together, higher melting point

Question 22

Properties of thermosoftening polymers ?

Answer 22

• made of individual, tangles polymer chains which are easily separated and melted by heat
• weak intermolecular forces between chains
• chains are easy to separate
• at lower temperatures
• less heat energy needed to break chains

Question 23

What do thermosetting polymers consist of ?

Answer 23

Polymer chains, which cross links so they do not melt when heated

Question 24

Examples of composites and properties ?

Answer 24

Carbon fiber and fiberglass (hard but brittle)

Question 25

What is the barber process used for ?

Answer 25

To manufacture ammonia which is used to produce nitrogen based fertilizers

Question 26

Haber process equation ?

Answer 26

Nitrogen + hydrogen <~> ammonia

Question 27

Describe the haber process ?

Answer 27

• purified gases (nitrogen and hydrogen) are passed over a catalyst of iron at a high temperature and high pressure
• some of the hydrogen and nitrogen reacts to form ammonia
• on cooling the ammonia liquefies and is removed
• remaining nitrogen and hydrogen is recycled

Question 28

What are the compounds of which all NPK fertilizers contain ?

Answer 28

Nitrogen, phosphorus, potassium

Question 29

How can phosphate rock be used in NPK fertilizers ?

Answer 29

Treated with nitric/sulfuric acid to produce soluble salts that can be used as NPK fertilizers

Question 30

What is phosphate rock a source of ?

Answer 30

Potassium chloride and sulfate

Question 31

What can phosphate rock be reacted with to create useful water-soluble compounds

Answer 31

Nitric acid :
- yields phosphoric acid and calcium nitrate
- the phosphoric acid is neutralized with ammonia, producing ammonium phosphate
Sulfuric acid :
- produces calcium phosphate and calcium sulfate (known as single superphosphate)
Phosphoric acid :
- calcium phosphate (tripe superphosphate)