| What is an ore? | Rock containing a metal or metal compound from which the metal is extracted |
| How does method of extraction depend on its reactivity? | The more the reactive the metal is the more stable the compound is, therefore more harder to extract the metal.
Most unreactive metals such as silver and gold occur in the ore as elements, the ores of all the other metals contain metal compounds which have to reduced to get the metal
Extraction being the strongest used to extract reactive metals.
Metals less reactive than carbon, the ores can be heated with carbon/carbon monoxide where the carbon displaces the metal from its compound. |
| What are the three raw materials involved in the extraction of iron and why is each of them used ? | Iron ore(Hematite)- Mainly iron(III) oxide with sand and other compounds mixed
Limestone (CaCO3)-Used to remove the impurities
Coke-this is made from coal(Almost pure carbon) |
| Give all the stages of the extraction of iron and what happens in each of those stages | Coke is burnt giving out heat
Carbon reacts with oxygen to give Carbon Dioxide
Carbon Monoxide is made
The carbon dioxide reacts with more coke to give out carbon monoxide
Iron(III) oxide is reduced
Carbon monoxide reacts with iron ore giving liquid iron
The limestone breaks down in the heat of the furnace
Calcium oxide that forms reacts with impurities(Sand) which is mainly silicon dioxide(silica) to form Calcium silicate which forms slag
Slag is used for road building
Waste gases
Carbon dioxide and Nitrogen |
| What is aluminium or called? | Bauxite |
| What is done about aluminium oxides high melting point? | Aluminium oxide is dissolved in molten cryolite which has a much lower melting point |
| At each electrode what happens during the extraction of aluminium? | At the cathode Aluminium is reduced
At the anode Oxygen is oxidized |
| State the properties of aluminium and how it makes aluminium useful | Its a good conductor of electricity- Used for electricity cables
Drinking cans/Cooking foil - Non toxic, light, doesn't corrode
Aeroplane manufacture- Low density, doesn't corrode, strong |
| Why do alloys have different physical features to that of the metals which are used to make the alloy? | Since the atoms of the two metals form a lattice which will be different from the original metals.
As the atoms in the lattice will be different sizes the layers of metal will not be able to slide past each other easily, therefore making it stronger. |
| Give places where mild steel might be used and why | Fridge, washing machine, cars, ships, machinery
Since it is hard and strong |
| Give places where stainless steel might be used and why | Cutlery, surgical equipments
Since its hard and doesn't rust |
| How does amount of carbon affect the strength of steel? | Carbon makes steel stronger but too much makes it brittle and hard to shape |
| What metals are added with iron to make stainless steel? | Nickel and chromium |
