What is an experiment to show rusting
- put 4 iron nails in 4 test tubes;
- distilled water, dry air, water with no dissolved air, salt water
- leave for 2 weeks
- results show that only test tubes 1 and 4 contain rust (distilled water and salt water)
- conclusion that oxygen AND water are needed for rusting
What is the chemical name for rust, and what is the word equation
-hydrated iron(III) oxide
iron + oxygen + water -> hydrated iron(III) oxide
Any reaction in which oxygen is added is called an OXIDATION reaction
Why is aluminium useful for car bodies
Aluminium doesn’t corrode in moist air, and so they don’t need much protection against corrosion. In air, a protective oxide layer forms on the surface of aluminium, protecting it from rust
Why do many metals corrode much faster now than ever before
There is much more atmospheric pollution than before, and so the acid rain amount has increased. Acid rain can have a pH value as low as 3, meaning that metals corrode much quicker in moist air
What are the most common materials used in a car
- metals and alloys (such as copper, steel and aluminium)
- plastics
- glass
- fibres
What does malleable mean
A metal that can be ‘beaten’ into a thin sheet
Why is it easy to separate iron from aluminium
Iron is magnetic, and aluminium is not; an electromagnet can easily attract any iron or steel parts
Why does recycling old car parts make sense
- extracting iron and aluminium from their ores takes enormous amounts of energy
- it avoids environmental damage to mining and quarrying
- it reduces the amount of rubbish that goes into landfill sites
What are the advantages of using steel in cars
- steel is stronger and harder than aluminium
- steel needed for a car body is cheaper than aluminium; cars made from steel cost less to buy
What are the advantages of using aluminium in cars
- aluminium is more malleable than steel
- aluminium doesn’t corrode as easily as steel, so the car body has a much longer lifetime
- aluminium is less dense than steel, so the mass of the car body is much less than the same car body made from steel. This also means that because it’s lighter, it has a better fuel economy than a car body made of steel
How much of the car (%) must be recyclable, and how much will it be in the future
85% of the car must be recyclable now, and it will increase to 95% in the future. This includes every part of the car, including the batteries
How is rust made on steel cars
- iron needs oxygen and water to rust
- the rust will then flake off of the surface of the iron; this allows more rusting to take place
