Topic 10- Using Resources

• Where do natural resources come from?

  The Earth, sea and air
• What can natural products be replaced with?

  Synthetic products
• What are some finite resources?

  Oil, coal, natural gas, minerals, nuclear fuels.
• What are some renewable resources?

  Trees, fresh water, food
• What are finite resources?

  Resources that aren't formed quickly enough to be considered replaceable so they will eventually become depleted.
• What are renewable resources?

  Resources that form at a similar or faster rate than we use them so they shouldn't become depleted.
• What are the benefits of extracting finite materials?

  Useful products made, provides jobs and brings money.
• What are some downsides of extracting ores?

  Bad for the environment as it uses energy, destroys habitats and produces lots of waste.
• What is sustainability?

  The ability to meet the needs of the present without compromising the ability of future generations to meet their own needs.
• What is bioleaching?

  The process of using bacteria to convert copper compounds in the ore into soluble copper compounds, which separates the copper from the ore. The leachate contains copper ions which can be extracted by electrolysis.
• What is a leachate?

  The solution produced by the bioleaching process.
• What is the process of phytomining?

  Plants are grown in soil that contains copper compounds which is taken in by the roots and then built up in the leaves. The plants are harvested, dried and burned, the ash contains soluble copper compounds which can be extracted by electrolysis or displacement.
• What is a Life Cycle Assessment?

  An evaluation of every stage of a product's life which could have an impact on the environment.
• What are the stages of the LCA?

  Getting the raw material (+transportation), manufacturing and packaging, use, disposal
• What are some problems of the LCA?

  Could be biased, effect of pollutants is hard to give a numerical value for, selective LCAs.
• What is potable water?

  Water that is safe to drink.
• How is potable water produced?

  Filtration and sterilisation.
• What is involved in the sterilisation process of water?

  Bubbling chlorine gas, using ozone or ultraviolet.
• What is involved in filtration process of water?

  Wire mesh and then gravel and sandbeds to filter out solid particles
• What is the distillation process?

  Boil the water until it evaporates, leaving the salt behind. Steam the condensed back into liquid which is potable water.
• What is the process of sewage treatment?

  Screening, sedimentation, effluent undergoes aerobic digestion and then released into environment, sludge undergoes anaerobic digestion where gas and digested waste produced (natural gas and fertiliser)
• What does the aerobic digestion do?

  Breaks down organic matter and microbes.
• What are ceramics?

  Non-metal solids with high melting points that aren't made from carbon-based compounds
• What are examples of ceramics?

  Clay, glass
• What are properties of clay?

  -soft material when it is dug up from ground

  -can be moulded into different shapes

  -hardens to form a clay ceramic when fired at high temperatures

  (ideal for pottery and bricks)
• What are properties of glass?

  -generally transparent

  -can be moulded when hot

  -brittle when thin

  -soda-lime glass: mixture of limestone, sand and sodium carbonate

  -borosilicate glass: higher melting point than soda-lime glass, made in the same way using a mixture of sand and boron trioxide
• What are composites made of?

  2 different materials (one embedded in the other)

  Fibres or fragments of a material (the reinforcement) are surrounded by a matrix acting as a binder
• What are the types of composites?

  Fibreglass, carbon fibre, concrete, wood
• What are the properties of fibreglass?

  -consists of fibres of glass embedded in a matrix of polymer (plastic)

  -low density

  -very strong

  -used in skis, boats and surfboards
• What are the properties of carbon fibre?

  -long chains of carbon atoms bonded together or nanotubes embedded in a polymer matrix

  -very strong

  -light

  -used in aerospace and sports car manufacturing
• What are properties of concrete?

  -made from aggregate (gravel and sand) embedded in a matrix of cement

  -very strong

  -used as a building material
• What are the properties of wood?

  -natural composite of cellulose fibres held together by an organic polymer matrix
• What does the properties of poly(ethene) depend on?

  Depends on the catalyst that was used and the reaction conditions (temperature and pressure):

  • low density polyethene: moderate temperature under high pressure- it's flexible and used for bags and bottles
  • high density polyethene: low temperature under low pressure, uses a catalyst- rigid and used for water tanks and drainpipes
• What are thermosoftening polymers?

  Contain individual polymer chains entwined together with weak forces between them- are able to be melted and remoulded
• What are thermosetting polymers?

  Contain monomers that can form cross links between polymer chains which hold them together in a solid structure- don't soften when heated, strong, hard and rigid
• What are the properties of ceramics?

  -insulators of heat and electricity

  -brittle

  -stiff

  -used for bricks and porcelain
• What are the properties of polymers?

  -insulators of heat and electricity

  -flexible

  -easily moulded

  -used in clothing and insulators in electrical items
• What are the properties of composites?

  -depend in the matrix and the reinforcement material

  -many uses
• What are the properties of composites?

  -depend on the matrix and reinforcement used

  -many uses
• What are the properties of metals?

  -malleable

  -good conductors of electricity and heat

  -ductile

  -shiny

  -stiff

  -used for electrical wires, car body-work and cutlery