Using resources (2) Flashcards
What are ceramics-
properties-
examples- (3)
non-metals with high melting points that aren’t made from carbon based compounds
Properties: malleable when molten, brittle when solidified
Clay
Soda-lime glass- mixture of limestone, sand and sodium carbonate
Borosilicate glass- sand and boron trioxide
Thermosoftening polymers-
Thermosetting polymers-
Thermosoftening polymers- contain individual polymer chains that are entwined with weak forest between chains
The weak forces allow it to be melted and remoulded
Thermosetting polymers- contain monomers that can form cross links between the polymer chains
They are strong, hard and rigid
what are composites and how are they generally structured
examples of composites and properties (4)
made of two materials with properties based on what they’re made of
a matrix surrounds fragments of a material (reinforcement)
Fibreglass- glass and plastic, strong
wood- a natural composite of cellulose fibres, strong
concrete- aggregate and cement, strong
carbon fibre- carbon, lightweight and rigid
Low-density Polymers formation and uses-
High-density polymers formation and uses-
Low-density Polymers- made from ethene at a moderate temperature under high pressure
It’s flexible and used for bags and bottles
High-density polymers- made from ethene at low temperatures and low pressures with a catalyst
It’s more rigid and used for water tanks
Examples of alloys:
Bronze=
Brass=
Steel=
Bronze= made of copper and tin
Brass= made of copper and zinc
Steel= made of iron and carbon
Corrosion-
Preventing corrosion-
Corrosion- when metals (iron and steel) react with air and water and are destroyed (rust)
Preventing corrosion- painting/ coating with plastic
electroplating
Oiling
Sacrificial method (adding a layer of more reactive metal on top of the iron)
Why does aluminium not fully corrode
When aluminium corrodes, it creates a layer of aluminium oxide, which acts as a barrier against corrosion and prevents any further destruction of the metal
What is a finite resource-
What is a renewable resource-
What is a finite resource- a resource that can be easily replenished (trees)
What is a renewable resource- a resource that will eventually run out and takes millions of years to create more (fossil fuels, nuclear fuels)
Phytomining-
Bioleaching-
Phytomining- growing plants in soil containing copper
harvest, dry and burn plants
the ash contains the metal compound
Bioleaching- using bacteria to convert copper compounds in the ore into soluble copper compounds
the leachate contains copper ions which can be extracted
metal recycling-
scrap iron and steel can be added to a furnace to reduce the amount of ore needed
What is a product lifecycle assessment-
What are the stages?
Problems with the product lifecycle assessment
analyses each stage of a product’s life and assesses its environmental impact
Extraction, manufacturing and packaging, use, disposal
problems- can be biased, shows a limited amount of impacts
What is potable water
Methods of production:
Potable water- water that is safe to drink with a relatively neutral Ph and limited dissolved substances
filtration- a wire mesh removes large soluble objects then gravel and sand beds filter out any other solids
sterilisation- water is sterilised to remove any micro-organisms
Water is distilled to remove salts and other dissolved substances
Waste water treatment
- sewage is screened to remove large debris
- it stands in a settlement tank and undergoes sedimentation
- heavier solids sink to the bottom to produce sludge and the lighter effluent floats on top
- The effluent is removed and treated by aerobic bacteria digestion (air is pumped through water to encourage aerobic bacteria to break down any organic matter, including other microorganisms)
- sludge is removed and broken down by anaerobic digestion
this releases methane and leaves fertiliser - water with toxic substances can be treated by adding chemicals, UV radiation or using membranes
The Haber Process-
a reversible reaction used to make ammonia from hydrogen and nitrogen on an industrial scale
- nitrogen obtained from the air
- hydrogen obtained from reacting methane with steam to form hydrogen and CO2
- The reacting gases are passed over an iron catalyst at 450*C and 200 atmospehres of pressure
the temperature and pressures used are a good compromise between maximum yield and rate of reaction and the price and safety of the reaction
NPK fertilisers
reactions of ammonia (2)
ammonia is useful to make fertilisers called NPK (nitrogen, phosphorus, potassium) fertilisers.
They help plants grow bigger, faster by providing them with nutrients
ammonia reacts with oxygen and water to make nitric acid.
This is good in fertilisers as it has two stores of nitrogen
You can react ammonia with nitric acid to make ammonia salts
reactions of phosphate rock:
nitric acid-
sulfuric acid-
Phosphoric acid-
nitric acid- produces phosphoric acid and calcium nitrate
sulfuric acid- produces calcium sulphate and calcium phosphate (single superphosphate)
Phosphoric acid- calcium phosphate (triple superphosphate)
