Using resources

Question 1

What are ceramics?

Answer 1

Non-metals with high melting points not made from carbon based compounds

Question 2

What are two common examples of ceramics?

Answer 2

clay

glass

Question 3

What are composites?

Answer 3

A material made up of two or more materials embedded in each other.

Question 4

What do the properties of composites depend on?

Answer 4

what the composite is made from

Question 5

What are some examples of composites? And what are their properties?

Answer 5

fibreglass (glass fibres embedded in polymers) - has a low density (from the polymers) but is strong (from the glass)
Carbon fibre (long chains of carbon joined together) - strong and light
Concrete (aggregate [any material made from fragments, eg. sand and gravel] embedded in cement) -very strong
Wood (natural composite)

Question 6

What influences the properties of a polymer?

Answer 6

how it’s made

what it’s made from

Question 7

What do the monomers a polymer is made from determine?

Answer 7

the type of bonds that form between the polymer chains

the weak bonds between the chains affect the properties of the polymer

Question 8

What are alloys and why do we use them?

Answer 8

Alloys are a metal with another element added to it to change the properties to make the metal more appropriate for its use. We use them instead of metals as they are better for its job, for example an alloy could be harder and stronger than the original metal.

Question 9

What are steels?

Answer 9

alloys of iron

Question 10

What properties does low carbon steel have? What can it be used for?

Answer 10

easily shaped

car bodies

Question 11

What properties does high carbon steel have? What can it be used for?

Answer 11

very hard and inflexible

blades for cutting tools or bridges

Question 12

What properties does stainless steel have? What can it be used for?

Answer 12

corrosion-resistant

cutlery or containers for corrosive substances

Question 13

What is bronze an alloy of?

Answer 13

copper and tin

Question 14

What is brass an alloy of?

Answer 14

copper and zinc

Question 15

What are gold alloys used for?

Answer 15

making jewellery

Question 16

What are aluminium alloys used for?

Answer 16

making aircraft

Question 17

What is rust?

Answer 17

hydrated iron (III) oxide
corrosion of iron

Question 18

What is corrosion?

Answer 18

Where metals react with substances in their environment and are gradually destroyed

Question 19

How does stainless steel prevent rust?

Answer 19

Stainless steel contains aluminium. When aluminium is exposed to air, it reacts to form aluminium oxide, which acts as a protective layer as none of the rest of the metal is exposed to air or water, meaning it can not rust.

Question 20

What experiment can you do to show that air and water are needed for rusting?

Answer 20

set up three test tubes:
in one, have an iron nail in water (with no air; boil the water and put a layer of oil on top to keep out air) to show that the iron won’t rust without air
in another, have air with no water (use calcium chloride to absorb any water) to show that water is needed to rust
in the third, have some water and air to show that the iron nail rusts with water and air

Question 21

How can you prevent rusting?

Answer 21

Coating the iron (eg. painting, coating with plastic, electroplating, oiling, greasing)
Sacrificial protection (placing a more reactive metal with the iron so that that metal reacts with the air instead of the iron)

Question 22

What are natural resources?

Answer 22

Resources that form without human input, eg cotton and fossil fuels

Question 23

What are renewable resources?

Answer 23

Resources that reform at a similar (or faster) rate than they are used, so do not run out.

Question 24

What are finite resources?

Answer 24

Non-renewable resources that will run out because they aren’t formed quickly enough to replaceable.

Question 25

What is sustainable development?

Answer 25

approach to development that takes account of present society whilst not damaging future generations

Question 26

How can we make finite resources last longer?

Answer 26

Reduce how much we use them (this also reduces how much needs to be produced, which will also reduce the use of anything needed to make them)

Question 27

How can the sustainability of copper be improved?

Answer 27

bioleaching (bacteria used to separate copper compounds) phytomining (growing plants in soil that contains copper so that copper builds up in the leaves, which can then be harvested, dried and burned so that copper can be extracted)

Question 28

Why are metals recycled?

Answer 28

recycling them uses much less energy than is needed to mine and extract new metal conserves the finite amount if each metal in the earth reduces the amount of waste that goes to landfill sites

Question 29

How can glass be recycled?

Answer 29

by being crushed, melted and reshaped to use in glass products alternatively, glass bottles can be reused without needing to be reshaped.

Question 30

What are life cycle assessments (LCA)?

Answer 30

an assessment that looks at every stage of a product's life to assess the impact it has on the environment

Question 31

What stages are considered in a life cycle assessment?

Answer 31

getting the raw materials (and how many stages are in this process) manufacturing and packaging use of the product (and how long it is used for) disposal of the product (eg. landfill, burnt)

Question 32

What are the disadvantages of life cycle assessments?

Answer 32

the effect of some pollutants are hard to give a numerical value to can be biased

Question 33

What is potable water?

Answer 33

Water that is safe to drink | isn't pure water as it does contain other dissolved substances

Question 34

How is rain water treated in the UK to become potable?

Answer 34

filtration - wire mesh screens out objects - sand beds filter out any other solid bits sterilisation - water is steralised to kill harmful baceria chemicals can be added, eg. fluoride

Question 35

Where does waste water come from?

Answer 35

Water used in homes (eg. shower, washing up, going to toilet) Agricultural systems (eg. slurry from animals, nutrient run offs from fields) Industrial processes

Question 36

Why does waste water need to be treated?

Answer 36

To remove any organic matter or harmful microbes before it can be put back into fresh water sources

Question 37

What happens in sewage treatment?

Answer 37

screening (removes large materials) sedimentation (heavier suspended solids sink to bottom of tank) and then... a) aerobic digestion (effluent water is treated by biological aerobic digestion to break down organic matter and microbes) water released into environment b) anaerobic digestion (sludge from bottom of settlement tank is removed and broken down by bacteria in anaerobic digestion) anaerobic digestion releases methane, which can be used as an energy source and the rest can be used as a fertiliser)

Question 38

What is a matrix?

Answer 38

a binder that holds together the reinforcement (fibres or fragments of a material) in a composite

Question 39

What is a reinforcement?

Answer 39

fibres or fragments of a material used in a composite

Question 40

What is the Haber process?

Answer 40

an industrial process used to make ammonia (which can then be used to make ammonium nitrate, which is used as a fertiliser) using the reaction: nitrogen + hydrogen -> ammonia

Question 41

Why does the Haber process work well on an industrial scale?

Answer 41

reactants aren't difficult or expensive to obtain - nitrogen is easily obtained from the air - hydrogen often comes from heating methane

Question 42

What industrial conditions are needed in the haber process?

Answer 42

pressure: 200 atmospheres temperature: 450°C catalyst: iron

Question 43

What are NPK fertilisers?

Answer 43

fertilisers that contain nitrogen, phosphate and potassium in the correct percentages of the elements for plants

Question 44

Why do farmers use fertilisers?

Answer 44

To provide enough nutrients (and to provide nutrients that have been lost from previous crops) for plant growth to increase their crop yield.

Question 45

How can ammonium nitrate (fertiliser) be produced? | two different ways

Answer 45

- in industry (at high concentrations in giant vats) | - in labs (at a much slower, smaller scale by using titrations and crystallisation)