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Flashcards in Using Resources Deck (111)
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1
Q

What are ceramics?

A

Non-metal solids with high melting points that aren’t made from carbon-based compounds.

2
Q

What kind of material is clay?

A

A soft material when it’s dug up so can be moulded into different shapes.

3
Q

What is clay ideal for?

A

Pottery and bricks made by shaping wet clay and then storing in a furnace.

4
Q

Give examples of ceramics:

A

Glass- can be moulded when hot and can be brittle when thin.
Clay- hardens to form a clay ceramic when fired at high temperatures.

5
Q

Most glass is made from…

A

…soda-lime glass.

6
Q

How is soda-lime glass made?

A

Heating a mixture of limestone, sand and sodium carbonate. When the mixture cools it comes out as glass.

7
Q

Compare Borosilicate glass to soda-lime glass:

A

Higher melting point.

Made in the same way as soda-lime glass (mixture of sand and boron trioxide.

8
Q

What are composites made of?

A

One material embedded in another. Fibres/ fragments of a material are surrounded by a matrix acting as a binder.

9
Q

Describe fibreglass:

A

Consists of fibres of glass embedded in a matrix made of polymer.
Low density.
Very strong.
Used for skis, boats and surfboards.

10
Q

Describe carbon fibre composites:

A

Have a polymer matrix like fibreglass.
Reinforcement made by either long chains of carbon atoms bonded together or from carbon nanotubes.
Strong and light.
Used in aerospace and sports car manufacturing.

11
Q

Describe concrete:

A

Made from aggregate (mixture of sand and gravel) embedded in cement.
Very strong.
Ideal as a building material (i.e skate parks)

12
Q

Describe wood:

A

Natural composite of cellulose fibres held together by an organic polymer matrix.

13
Q

The properties of polymers depend on…

A

…what monomers they are made from and the condition under which they are made.

14
Q

What is the difference between thermosetting polymers and thermosoftening polymers?

A

Thermosoftening melt when they are heated.

Thermosetting do not melt when heated.

15
Q

Explain how low density and high density poly(ethene) are both produced from ethene:

A

LD poly(ethene)is made from ethene at a moderate temperature under a high pressure with a catalyst. HD poly(ethene) is made from a lower pressure and temp ethene with a different catalyst.

16
Q

Describe thermosoftening polymer structures:

A

Thermosoftening contain individual polymer chains entwined together with weak forces between the chains.

17
Q

Describe thermosetting polymer structures.

A

Thermosetting contain monomers that can form cross links between the polymer chains, holding the chains together in a solid structure. They are strong, hard and rigid.

18
Q

What are most composites made of?

A

Two materials, a matrix or binder surrounding and binding together fibres or fragments of the other material, which is called the reinforcement.

19
Q

Recall some composites:

A

Wood, fibreglass, carbon fibre, concrete…

20
Q

Water of appropriate quality is…

A

…essential for life.

21
Q

What should the quality of water be for humans?

A

Have sufficiently low levels of dissolved salts and microbes.

22
Q

What is potable water?

A

Water that is safe to drink.

Is not pure in the chemical sense because it dissolved substances.

23
Q

The methods used to produce potable water depend on…

A

…available supplies of water and local conditions.

24
Q

Describe rain water in the United Kingdom:

A

Provides water with low levels of dissolved substances (fresh water) that collects on the ground and in lakes and rivers.

25
Q

Most potable water is produced by…

A

Choosing an appropriate source of fresh water, passing the water through filter beds, sterilising.

26
Q

Sterilising agents used for potable water include:

A

Chlorine, ozone or ultraviolet light.

27
Q

What happens if supplies of fresh water are limited?

A

Desalination of salty water or sea water may be required.

28
Q

How can desalination be carried out?

A

By distillation or by processes that use membranes such as reverse osmosis. These processes require large amounts of energy.

29
Q

Distinguish between purer water and potable water:

A

Potable water is water that has been treated or is naturally safe for human consumption with some dissolved substances. Pure water only contains H2O molecules.

30
Q

Describe the treatment of ground water:

A

Ground water needs to be filtered (through wire mesh) and sterilised (bubbling chlorine gas through or by using ozone or ultraviolet light. Salty water needs

31
Q

Describe the treatment of salty water:

A

Needs to be distilled (titration to neutralise, yellow flame test for sodium and add nitric acid and silver nitrate solution to detect white precipitates of chloride ions, then distil normally and check twice for removal of sodium chloride by doing a pH test).

32
Q

Humans use the Earth’s resources to provide…

A

…warmth, shelter, food, transport.

33
Q

What do natural resources supplemented by agriculture provide?

A

Food, timber, clothing, fuels.

34
Q

What provides energy and materials?

A

Finite resources from the Earth, oceans and atmosphere.

35
Q

How does Chemistry play a role in improving agricultural and industrial processes?

A

Provides new products in a sustainable development, which is development which meets the needs of current generations without compromising the ability of future generations to meet their own needs.

36
Q

Give some examples of natural resources that are supplemented or replaced by agricultural/synthetic products:

A

Wool, cotton, silk, rubber, wood.

37
Q

What is wood used for and replaced by?

A

used for clothes and carpets replaced by acrylic fibre or poly(propene).

38
Q

What is cotton used for and replaced by?

A

Cotton used for clothes and textiles replaced by polyester.

39
Q

What is silk used for and replaced by?

A

Clothes and replaced by nylon.

40
Q

What is rubber used for and replaced by?

A

Tyres and washers and replaced by various synthetic polymers, poly(butadiene).

41
Q

What is wood used for and replaced by?

A

Construction and replaced by PVC, composites or MDF.

42
Q

What are finite resources?

A

Resources that are being used up faster than they are being replaced like coal and crude oil.

43
Q

What are renewable resources?

A

Resources that are replaced at the same amount of time that they are being used like wind turbines and solar panels.

44
Q

What do urban lifestyles and industrial processes produce?

A

Large amounts of waste water that require treatment before being released into the environment.

45
Q

Why do sewage and agricultural waste water require removal of to be potable?

A

Removal off organic matter and harmful microbes.

46
Q

Industrial waste water may require removal of…

A

…organic matter and harmful chemicals.

47
Q

What does sewage treatment include?

A

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

48
Q

Comment on obtaining potable water from waste to obtaining potable water from seawater and fresh water:

A

Treatment requires more processes than treating fresh water but uses LESS energy than the desalination of seawater.

49
Q

The Earth’s resources of metal ores are…

A

…limited.

50
Q

Copper ores are becoming…

A

…scarce.

New ways of extracting copper from low-grade ores include phytomining, and bioleaching.

51
Q

New ways of extracting copper from low-grade ores include…

A

… phytomining, and bioleaching.

52
Q

What do phytomining and bioleaching avoid?

A

Traditional mining methods of digging, moving, and disposing of large amounts of rock.

53
Q

What is phytomining?

A

A way of extracting copper from low-grade ores which uses plants to absorb metal compounds. The plants are harvested and then burned to produce ash which contains metal compounds.

54
Q

What is Bioleaching?

A

Uses bacteria to produce Leachate solutions that contain metal compounds.

55
Q

The metal compounds can be processed to…

A

Obtain the metal.

56
Q

Give an example of processing metal compounds:

A

Copper can be obtained from solutions that of copper compounds by displacement using scrap iron or by electrolysis.

57
Q

What are the stages carried out to assess environmental impacts of products (LCAs)?

A

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.

58
Q

Which uses can be easily quantified?

A

Water, resources, energy sources and production of some wastes.

59
Q

What makes an LCA not a purely objective process?

A

It is less straightforward to allocate numerical values to pollutant effects.

60
Q

Give a disadvantage of LCAs:

A

Selective if abbreviated LCAs can be devised to evaluate a product but these can be misused to reach pre-determined conclusions.

61
Q

Why might a company devise a selective or abbreviated LCA?

A

To support claims for advertising purposes.

62
Q

What are the raw materials use to make plastic bags and paper bags?

A

Crude oil for plastic, timber for paper.

63
Q

Describe the manufacturing and packaging of a plastic bag:

A

The compounds needed to make the plastic are extracted from crude oil by fractional distillation followed by cracking and then polymerisation.

64
Q

Give an advantage for the manufacturing and packaging of plastic bags:

A

Waste is reduced as the other fractions of crude oil have other uses.

65
Q

Describe the manufacturing and packaging of paper bags:

A

Pulled timber is processed using lots of energy. Lots of waste is made.

66
Q

Give some uses of plastic bags:

A

Can be reused. Can be used for other things as well as shopping.

67
Q

Give a use of paper bags:

A

Usually only used once.

68
Q

State the product disposal of plastic bags:

A

Recyclable but not biodegradable and will take up space in landfill and pollute land.

69
Q

Product disposal of paper bags:

A

Biodegradable, non-toxic, can be recycled.

70
Q

The reduction in use, reuse and recycling of materials by end users, reduces the use of…

A

… limited resources, use of energy sources, waste and environmental impacts.

71
Q

Limited raw materials are used to produce:

A

Metals, glass, building materials, clay ceramics, and most plastics.

72
Q

Much of the energy used for recycling processes comes from…

A

…limited resources.

73
Q

What does obtaining raw materials from the Earth by quarrying and mining cause?

A

Environmental impacts.

74
Q

How can glass bottles be reused?

A

Crushed and melted to make different glass products.

75
Q

How can metals be recycled?

A

By melting and recasting or reforming into different products.

76
Q

The amount of separation required for recycling depends on…

A

… the material and the properties required of the final product.

77
Q

What is corrosion?

A

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

78
Q

What is rusting an example of?

A

Corrosion.

79
Q

Which chemicals are necessary for iron to rust?

A

Air and water.

80
Q

How can corrosion be prevented?

A

By applying a coating that acts as a barrier, such as greasing, painting or electroplating.

81
Q

What type of barrier does aluminium have against corrosion?

A

An oxide coating that protects the metal from further corrosion.

82
Q

Some coatings are reactive and contain…

A

…a more reactive metal to provide sacrificial protection e.g zinc is used to galvanise iron.

83
Q

What is the Haber process used for?

A

To make ammonia from hydrogen and nitrogen, which can be used to produce nitrogen-based fertilisers.

84
Q

What is the chemical equation for the Haber Process?

A

N3(g) + 3H2(g) = 2NH3(g) (+heat)

85
Q

What is the Haber Process reaction suited for?

A

An industrial scale as the reactants aren’t too difficult or expensive to obtain.

86
Q

What is the first step of the Haber Process?

A

The reactant gases are passed over an iron catalyst. A high temperature (450°C) and a high pressure (200 atmospheres) are used.

87
Q

What is the second step of the Haber Process?

A

Because the reaction is reversible (it occurs in both directions), some of the ammonia produced converts back into hydrogen and nitrogen again. Eventually reaches a DYNAMIC EQUILIBRIUM.

88
Q

What is the third step of the Haber Process?

A

The ammonia is formed as a gas, but as it cools in the condenser it liquefies and is removed. The unused hydrogen condenser it liquefies and removed. The unused hydrogen and nitrogen are recycled.

89
Q

What is the fourth step of the Haber Process?

A

The ammonia produced can then be used to make ammonium nitrate - a very nitrogen-rich fertiliser.

90
Q

Where does the hydrogen used in the Haber Process obtained from?

A

Reacting methane with steam to form hydrogen and carbon dioxide.

91
Q

Where is nitrogen obtained from for the Haber Process?

A

From the air, which are 78% nitrogen.

92
Q

Most metals in everyday use are…

A

…alloys.

93
Q

What is Bronze?

A

An alloy of copper and tin.

94
Q

What is Brass?

A

An alloy of copper and zinc.

95
Q

What is Gold (used as jewellery)?

A

Usually an alloy with silver, copper and zinc.

96
Q

The percentage of gold in the alloy is measured in…

A

…carats.

97
Q

What are the measurements for carats (gold)?

A

24 carat =100% (pure gold), 18 carat = 75% gold.

98
Q

What are steels?

A

Alloys of iron that contain specific amounts of carbon and other metals.

99
Q

Describe high carbon steel:

A

Strong but brittle.

100
Q

Low carbon steel is…

A

…softer and more easily shaped (malleable).

101
Q

Which steels are resistant to corrosion?

A

Steels contains chromium and nickel (stainless steels).

102
Q

Aluminium alloys are…

A

…low density.

103
Q

Compound of which elements are used as fertilisers to improve agricultural productivity?

A

Nitrogen, phosphorus and potassium.

104
Q

What are NPK fertilisers?

A

Formulations of various salts and nitric acid.

105
Q

Mining obtains:

A

Potassium chloride, potassium solfataras, and phosphate rock.

106
Q

Why can phosphate rock not be used directly as a fertiliser?

A

The salts on the rock are insoluble so plants can’t use them as nutrients.

107
Q

What can ammonia be used to manufacture?

A

Ammonium salts and nitric acid.

108
Q

What can phosphate rock be treated with to make them fertilisers?

A

Nitric acid or Sulphuric acid to produce soluble salts.

109
Q

Which salts are produced when phosphate rock is treated with nitric acid?

A

Phosphoric acid and calcium nitrate.

110
Q

Which salts are produced when phosphate rock is treated with sulphuric acid?

A

Calcium surface and calcium phosphate (mixture known as single superphosphate).

111
Q

Which salts are produced when phosphate rock is treated with phosphoric acid?

A

Calcium phosphate (can be called triple superphosphate).