Using Resources Flashcards
What are natural resources used for?
Food, timber, clothes, fuels
What are finite resources used for?
Processed to provide energy and materials
What do humans use earths resources for
To provide warmth, shelter, food, transport
How do you obtain potable water in areas which do not have a lot of rainfall?
Desalination: either by doing
Distillation or
Reverse osmosis
What does sewage treatment include
screening (remove large bits of material) and grit (small bits of stone and sand) removal
Sedimentation- heavier solids sink to produce sewage sludge. Lighter effluent (liquid waste) floats on top
Aerobic digestion to reduce and treat effluent- safe water released back into environment
Sludge is broken down by bacteria in anaerobic digestion, produces methane gas used as energy source, remaining waste used as fertiliser
How is potable water produced from fresh water?
(Rivers/rain) water goes into reservoir, then screening mesh to filter any large objects, then goes through filter beds to filter out any undissolved solids. Then add (chlorine/ozone/ultraviolet light) to sterilise the water, killing any microbes
What are alloys?
mixtures of metals (and sometimes non-metals).
What is bronze an alloy of?
copper and tin.
What is bronze used for and why?
statues and decorative items because it is tough and resistant to corrosion.
What is brass an alloy of?
copper and zinc.
What is brass used for and why?
musical instruments, door fittings, and taps because it is workable and malleable, and harder than copper.
What is a use of aluminium alloys and why?
Aluminium alloys are used in aircrafts, technology, vehicle bodies: because they are lightweight, strong, and have low density.
What other metals are normally added to gold to make alloys of gold?
Silver, copper, zinc, and polladium.
What is steel an alloy of?
Iron with carbon/other elements.
What types of steel are there?
Low carbon steel, high carbon steel, stainless steel(chromium and nickel)- hard and resistant to corrosion
What is a difference between high carbon steel and low carbon steel?
High carbon steel is strong but brittle, while low carbon steel is softer and more easily shaped.
What is a use of low and high carbon steel, and stainless steel?
Low carbon steel is used in shipbuilding, wire, vehicle bodies, and domestic appliances; high carbon steel is used for cutting tools, springs, and coils; stainless steel is used for cutlery.
What is rust? Conditions?
Rust is the corrosion of iron.
Oxygen and water
How can corrosion/rust be prevented?
Rust can be prevented by protecting iron from moisture and air- coating such as oil, painting, electroplating (thin layer of metal on inside metal)
-sacrificial protection- more reactive metal coating on the metal(more reactive corrodes and forms a protective layer- galvanising)
Why DOENST Aluminium corrode much?
It quickly forms an oxide coating which protects the metal from further corrosion
How is soda lime glass made?
Heating a mixture of sand, sodium carbonate, and limestone
What is borosilicate glass? And how is it different from soda like glass?
Made from sand and boron trioxide
It melts at higher temps than soda like glass
How are clay ceramics made?
Shaping wet clay and heating it in a furnace to harden
What is a composite?
2 materials- reinforcement surrounded by matrix or binder
- different properties to the materials in them
