Aluminium

200 years ago, aluminium was a more precious metal than gold. This is because:
1. it is a rarer metal than gold
2. gold is a very common element in the Earth's crust.
3. aluminium is a very common element in the Earth's crust, but very hard to extract.
4. people in those days didn't have the technology to heat up furnaces to high temperatures.
Aluminium is extracted from its ore which is called:
1. Bauxite
2. Haematite
3. Loctite
4. Holdmetite
Which one of these properties does NOT apply to aluminium?
1. It is easy to cut and shape.
2. It is a good conductor of electricity.
3. It is a good conductor of heat.
4. It is magnetic
Aluminium is extracted using:
1. a blast furnace.
2. an oxy-acetylene flame (very hot).
3. electrolysis cell.
4. electric arc furnace.
Trains and aeroplanes often have bodies that are made of unpainted aluminium. Which one of these is the correct reason for this?
1. Alumnium is very unreactive with oxygen.
2. Aluminium is very reactive and rapidly forms a tough oxide layer, protecting the metal underneath.
3. Paints do not bind well to aluminium.
4. It is easier to remove graffiti from a plain aluminium surface than a painted surface.