C10: Using resources Flashcards
Define sustainable development
Development that meets the need of current generations without compromising the ability of future generations to meet their own needs
give 4 examples of what natural resources are used for
- food,
- timber
- clothing
- fuels
describe what synthetic resources are and what their use is
- They are resources made by scientists.
- They can replace or supplement natural resources.
Define finite resources and give an example
Resources that will eventually run out.
example: fossil fuels
Define renewable resource and give an example
- sources of power that quickly replenish
themselves and can be used again - wood
Define potable water
water that is safe to drink
Give three sources of fresh water
- rivers
- lakes
- groundwater
What is the difference between potable and pure water
potable water contains safe levels microbes and dissolved substances whereas pure water does not
Describe how potable water is
produced in the UK from rain
water collected in lakes and
river
- Choose an appropriate source of fresh water
- Pass the water through filters to remove large
objects - Sterilize the water to kill any microbes using ozone,
chlorine or UV light
What are the sterilizing agents for potable water and evaluate them
- chlorine, ozone or ultraviolet light
- chlorine is a toxic gas so the amount added to water has to be carefully monitored
- using ultraviolet to kill microbes avoids adding chemicals to the water but is more expensive
When is desalination used
- when fresh water supplies are limited
- when only salty/sea water is available
How is desalination carried out
- by distillation or reverse osmosis
- these require large amounts of energy
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How is wastewater produced
- urban lifestyles and industrial processes produce large amounts of wastewater
Give the stages of sewage
treatment
- screening and grit removal:
- sedimentation to produce sewage sludge and effluent
- anaerobic digestion of sewage sludge
- aerobic biological treatment of effluent.
Describe the screening and grit removal stage
sewage passes through a metal grid that filters out large objects
Describe the sedimentation stage
- the sewage is left so that solid sediments settle out of the water.
- The sediments sink to the bottom of the tank.
- produces sludge and effluent
Describe the anaerobic digestion of sewage sludge stage
- Bacteria are added to break down the sludge anaerobically.
- The remaining sludge is dried and produces biogas which can be used as a fuel.
Describe the aerobic biological treatment of effluent stage
- Bacteria are added to the effluent and break this down by aerobic respiration.
- The bacteria then settle out of the water.
- The water is now safe enough to be released back into the environment.
what is involved in traditional mining
methods
traditional mining methods include
- digging, moving and disposing of large amounts of rock.
Explain why scientist are
looking for new ways to extract
metals from their ores
- Metal ores are a finite resource
- Extracting metals requires a lot of energy
Describe what is meant by a low-grade copper ore
- a rock ore does not contain much copper
Name two alternative processes
to extract copper from low-grade ores
- Phytomining
- Bioleaching
Describe the process of phytomining
- uses plants to absorb metal compounds from the soil
- Harvest and burn the plants to produce ash
- The ash contains the metal compound
- the ash is processed by electrolysis or displacement with scrap metal
Describe the process of bioleaching
- Grow bacteria near the metal ore
- Bacteria produce leachate solutions that contain metal
compound - Process the leachate by electrolysis or displacement with scrap metal
Explain why phytomining and
bioleaching is more
sustainable
avoid the digging, moving and disposing of large amounts of rock associated with traditional mining techniques
Give a disadvantage of phytomining and bioleaching
- too slow to carry out
Define a Life Cycle Assessment
- looking at the whole life of a product and - assessing its impact on the environment and sustainability.
Describe the four categories of
life cycle assessments
-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
State the objective or
quantifiable parts of the LCA
- Amount of water used
- Waste produced
what are the advantages and disadvantages of recycling (3/3)
adv:
- less acid rain (pollution)
- metal ore reserves last longer
- less waste and landfill
disadv:
- collection/ transport problems
- cost of transport
- difficult to separate metals from appliances
List the four things that can
happen when someone finishes
with a product and outline the
impact in each case
- It can be added to a landfill
- Causes habitat loss - It can be incinerated (combusted)
- Can produce useful energy
- Could be incomplete combustion and results in harmful pollutants being released - it can be used
- it can be recycled
Describe how metals are recycled
Melting them down and casting them into a new shape
Describe the practical used to analyse and purify water making it safe to drink : include objective and method
objective: To determine the amount of dissolved solid in samples of water
method:
- Use the universal indicator paper to determine the pH of the water sample
- Accurately weigh an empty evaporating basin to two decimal places
- Add 25 cm3 of water sample A into the evaporating basin
- Heat the evaporating basin on a tripod and gauze using a Bunsen burner until the solids start to form and the majority of water has evaporated
- Leave for the remaining water to evaporate off
- Weigh the cooled evaporating basin again and calculate the mass of the solids that were dissolved in the water.
Describe the practical used to purify a water sample by distillation: include objective and method
- Add the water sample to the conical flask and set up the apparatus for distillation as shown in the diagram
- Heat the water using the Bunsen burner until boiling occurs
- Reduce the heat so that the water boils gently for some time
- The distilled water will collect in the cooled test tube
- Collect about 2 cm depth of water in this way, then stop heating
- Analyse the water you have distilled by determining its boiling point
What is corrosion and how is it prevented?
- the destruction of materials by chemical reactions with substances in the environment e.g. rusting
- applying a coating that acts as a barrier, such as greasing painting or electroplating. these stop air or water contact
Describe the sacrificial protection
- some coatings are reactive and may contain corrosion inhibitors or a more reactive metal
- if two metals are in contact the more reactive meal will corrode instead of the less reactive one
What is rusting?
Rusting is the corrosion of iron
Why are materials
made from aluminium
protected from
corrosion?
Materials made from aluminium form an oxide layer
which acts as a protective layer preventing further
corrosion
Name 3 methods to
prevent iron rusting
● Coat iron in paint/oil/grease
● Galvanize the iron with a more reactive metal
(the more reactive metal provides sacrificial
protection)
● Electroplating
What is needed for
iron to rust?
● Oxygen and water
What is an alloy?
A mixture of metals
Describe the compounds and the uses of :
bronze
brass
gold
bronze: an alloy of copper and tin: for making statues and decorative objects
brass: an alloy of copper and zinc : producing water taps and door fittings
gold: used as jewellery is alloy with silver, copper, zinc
Describe the compounds and the uses of:
- aluminium-magnesium
- steels
aluminium-magnesium : alloys are low density and used in aerospace manufacturing
steels: alloys of iron that contain specific amounts of carbon and other metals
Give 2 properties of
stainless steel
containing chromium and nickel
- hard
- resistant to corrosion
How are the properties of polymers determined?
- the properties of polymers depend on what monomers they are made from and the conditions under which they are made
Describe the structures of thermosoftening polymers
- soften easily on heating and can then be remoulded, keeping the new shape on cooling
- polymer molecules are attracted to each other by weak intermolecular forces
Why do
thermosoftening
polymers melt when
heated?
They have weak crosslinks/intermolecular forces between the polymer chains which require little energy to overcome
Describe the structure of thermosetting polymers
- do not melt when heated
- they have strong covalent bonds between chains which are not easily overcome
How is soda-lime
glass made?
By heating a mixture of sand, sodium carbonate and limestone
. How is borosilicate
glass made?
Sand and boron trioxide
- melts at a higher temperatures than soda-lime glass
Name 3 properties
common to both types
of glass
● Transparent
● Brittle
● Hard
How are ceramics
made?
Shaping wet clay and heating in a furnace
Give 3 properties of
ceramics
● Hard
● Resistant to chemical attack
● Brittle
How are composites formed?
- fibres or fragments of one material ( reinforcement) are surrounded by a binder/matrix material that holds these fibres/fragments together
What are
composites?
They are made up of 2 materials producing a product with improved properties for a particular use
Name the 2
materials that make up
composites
● Matrix (or binder)
● Reinforcement (which is surrounded by the
matrix)
Give 2 uses of
composites
● Carbon fibre – car
● Sand and gravel mixed with water – cement
Outline the key points of Haber Process
a) the purified H² and N² gases are passed over Fe catalyst at a high temperature ( about 450℃) and a high pressure ( 200 atm)
b) Fe speeds up the rate of reaction, so that a lower temperature could be used in the process
c) Some of the hydrogen and nitrogen react to form ammonia
d) The reaction is reversible so ammonia breaks down again into nitrogen and hydrogen
e) on cooling, the ammonia liquefies and is removed. The remaining hydrogen is recycled
What is a use of
manufacturing ammonia
using the Haber
process
To make nitrogen-based fertilisers
What are the raw
materials for the Haber
process and give sources of it?
Nitrogen and hydrogen
- air
- natural gas
Explain why the Haber Process uses high temperature and pressure conditions. Why is this a compromise
- the conditions are a compromise between rate and the yield:
- the reaction is exothermic. An optimum temperature of 450℃ is used. Using a lower temperature which give a higher yield, but the rate of NH3 production would be too slow
- a pressure of 200N atm is used. Using a higher pressure would give a higher yield, but would be too expensive due to cost of energy
What happens to
the gases in the cooling
chamber?
● Gases are cooled
● Ammonia condenses into a liquid
● The unused nitrogen and hydrogen are
recycled and returned back into the reactor
Give 2 reasons why
fertilisers are used when
growing crops
● Increase crop yield
● Increase rate of growth
What are the 3
essential elements
found in fertilisers?
● Nitrogen
● Phosphorus
● Potassium
What can ammonia
be used to manufacture?
Ammonium salts and nitric acid
How are potassium
chloride, potassium
sulfate and phosphate
rock obtained?
from mining
How is industrial production of NPK fertilisers achieved?
- Ammonia can be used to manufacture ammonium salts.
- the ammonium sulfate, phosphate and nitrate can be produced by reaction of ammonia with the requisite acid
How is the phosphate rock utilised in the production of fertilisers?
- phosphate rock is reacted with nitric acid to produce phosphoric acid and calcium nitrate
- phosphate rock can be reacted 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
What is produced
when nitric acid reacts
with phosphate rock?
Phosphoric acid
What is produced
when sulphuric acid
reacts with phosphate
rock?
Single superphosphate
What is produced
when phosphoric acid
reacts with phosphate
rock
Triple superphosphate
