Using Resources Flashcards
What is sustainable development?
Development that meets the needs of current generations without compromising the ability of future generations to meet their own needs
What is potable water
Water that is safe to drink
What is the difference between pure water and potable water?
Pure water contains only H20
Potable water is drinkable water - could contain minerals
How do you test for water?
Anhydrous copper sulphate turns from white to blue
Cobalt chloride paper turns from blue to pink
Describe two desalination techniques
Distillation
Reverse osmosis - forcing water through a fine membrane
Why is desalination only used where fresh water is in low supply?
It requires large amounts of energy
How is potable water produced in the UK?
- An appropriate source of fresh water is chosen
- Water is filtered
- Water is sterilised
How can water be sterilised?
3 ways
Chlorine
Ozone
UV light
How is sewage treated?
- Filtered to remove large solids and grit
- Sedimentation (dirt sinks to the bottom) separates effluent and sludge
- Effluent treated with aerobic microbes
- Sludge treated with anaerobic microbes, produces methane (used for energy) and leftover organic material (used for fertiliser)
What are the three types of water available to make potable?
Ground water
Salt water
Waste water (sewage)
What are the two main methods for extracting low-grade ores?
Phytomining
Bioleaching
What is phytomining?
Plants absorb metal ores, then are harvested and burned to produce ash containing metal compounds
What is bioleaching?
Uses bacteria to feed on metal ores and produce leachate solutions containing metal compounds. These can be processed to obtain the pure metal (E.g. electrolysis)
What are life cycle assessments?
They assess the environmental impact of products
What are the stages of life cycle assessments?
- Extracting and processing raw materials
- Manufacturing and packaging
- Use and operation during lifetime
- Disposal and transportation
(+Distribution at each stage)
What are the disadvantages of life cycle assessments?
They can be misused for advertising purposes
What is corrosion?
The destruction of materials by chemical reactions with substances in the environment
What is needed for iron to rust?
Air and water
What ways can corrosion be prevented?
Applying a coating to act as a barrier (E.g. painting)
Sacrificial protection (more reactive coatings)
What is bronze an alloy of?
Copper and tin
What is brass an alloy of?
Copper and zinc
Why is aluminium used in alloys?
To lower the density
What percentage of gold is in 24K?
100%
What percentage of gold is in 18K?
75%
What is a property of steels containing chromium and nickel?
Stainless steel
Hard and resistant to corrosion
Why are alloys stronger than pure metals?
Made from different sized atoms
Distorts the regular layers of metal atoms
Stops the layers sliding over each other
What is stainless steel made of?
Iron, carbon, chromium, and nickel
What are the properties of low carbon steel?
Soft and easily shaped
What are the properties of high carbon steel?
Strong and brittle
What is low carbon steel used for?
Frames, bridges, etc.
What is high carbon steel used for?
Cutting tools, springs, high strength wires
What are thermosoftening polymers?
Polymers that melt when heated
What are thermosetting polymers?
Polymers that don’t melt when heated
What do the properties of polymers depend on?
What monomers they were made from and in what conditions
What is soda-lime glass made from?
Sand, sodium carbonate, and limestone
What is borosilicate glass made from and why?
Sad and boron trioxide
Melts at higher temperatures
How are ceramics made?
Shaping wet clay and heating in a furnace
What is the Haber process? (give the word equation)
Nitrogen + Hydrogen ⇋ Ammonia
What are the conditions required for the Haber process?
Passed over an iron catalyst
High temperature (450°C)
High pressure (200 atmospheres)
Where does the hydrogen used for the Haber process come from?
Natural gas
Where does the nitrogen used in the Haber process come from?
The air
What three elements are in NPK fertilisers?
Nitrogen
Phosphorus
Potassium
What 3 acids can be reacted with mined phosphate rock to produce fertiliser salts?
Phosphoric acid
Sulphuric acid
Nitric acid
What salt is made when phosphate rock reacts with sulphuric acid?
Single superphosphate
What salt is made when phosphate rock reacts with nitric acid?
Calcium nitrate
What salt is made when phosphate rock reacts with phosphoric acid?
Triple superphosphate
