Using Resources Flashcards
What are ceramics?
Non-metal solids with high melting points that aren’t made from carbon-based compounds.
What kind of material is clay?
A soft material when it’s dug up so can be moulded into different shapes.
What is clay ideal for?
Pottery and bricks made by shaping wet clay and then storing in a furnace.
Give examples of ceramics:
Glass- can be moulded when hot and can be brittle when thin.
Clay- hardens to form a clay ceramic when fired at high temperatures.
Most glass is made from…
…soda-lime glass.
How is soda-lime glass made?
Heating a mixture of limestone, sand and sodium carbonate. When the mixture cools it comes out as glass.
Compare Borosilicate glass to soda-lime glass:
Higher melting point.
Made in the same way as soda-lime glass (mixture of sand and boron trioxide.
What are composites made of?
One material embedded in another. Fibres/ fragments of a material are surrounded by a matrix acting as a binder.
Describe fibreglass:
Consists of fibres of glass embedded in a matrix made of polymer.
Low density.
Very strong.
Used for skis, boats and surfboards.
Describe carbon fibre composites:
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.
Describe concrete:
Made from aggregate (mixture of sand and gravel) embedded in cement.
Very strong.
Ideal as a building material (i.e skate parks)
Describe wood:
Natural composite of cellulose fibres held together by an organic polymer matrix.
The properties of polymers depend on…
…what monomers they are made from and the condition under which they are made.
What is the difference between thermosetting polymers and thermosoftening polymers?
Thermosoftening melt when they are heated.
Thermosetting do not melt when heated.
Explain how low density and high density poly(ethene) are both produced from ethene:
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.
Describe thermosoftening polymer structures:
Thermosoftening contain individual polymer chains entwined together with weak forces between the chains.
Describe thermosetting polymer structures.
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.
What are most composites made of?
Two materials, a matrix or binder surrounding and binding together fibres or fragments of the other material, which is called the reinforcement.
Recall some composites:
Wood, fibreglass, carbon fibre, concrete…
Water of appropriate quality is…
…essential for life.
What should the quality of water be for humans?
Have sufficiently low levels of dissolved salts and microbes.
What is potable water?
Water that is safe to drink.
Is not pure in the chemical sense because it dissolved substances.
The methods used to produce potable water depend on…
…available supplies of water and local conditions.
Describe rain water in the United Kingdom:
Provides water with low levels of dissolved substances (fresh water) that collects on the ground and in lakes and rivers.
Most potable water is produced by…
Choosing an appropriate source of fresh water, passing the water through filter beds, sterilising.
Sterilising agents used for potable water include:
Chlorine, ozone or ultraviolet light.
What happens if supplies of fresh water are limited?
Desalination of salty water or sea water may be required.
How can desalination be carried out?
By distillation or by processes that use membranes such as reverse osmosis. These processes require large amounts of energy.
Distinguish between purer water and potable water:
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.
Describe the treatment of ground water:
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
Describe the treatment of salty water:
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).
Humans use the Earth’s resources to provide…
…warmth, shelter, food, transport.
What do natural resources supplemented by agriculture provide?
Food, timber, clothing, fuels.
What provides energy and materials?
Finite resources from the Earth, oceans and atmosphere.
How does Chemistry play a role in improving agricultural and industrial processes?
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.
Give some examples of natural resources that are supplemented or replaced by agricultural/synthetic products:
Wool, cotton, silk, rubber, wood.
What is wood used for and replaced by?
used for clothes and carpets replaced by acrylic fibre or poly(propene).
What is cotton used for and replaced by?
Cotton used for clothes and textiles replaced by polyester.
What is silk used for and replaced by?
Clothes and replaced by nylon.
What is rubber used for and replaced by?
Tyres and washers and replaced by various synthetic polymers, poly(butadiene).
What is wood used for and replaced by?
Construction and replaced by PVC, composites or MDF.
What are finite resources?
Resources that are being used up faster than they are being replaced like coal and crude oil.
What are renewable resources?
Resources that are replaced at the same amount of time that they are being used like wind turbines and solar panels.
What do urban lifestyles and industrial processes produce?
Large amounts of waste water that require treatment before being released into the environment.