C1.4 Flashcards
Why are only a few metals found pure in the ground
They have to very unreactive such as gold and platinum, otherwise if they weren’t, when they come in contact with oxygen they will oxidase and form compounds
What are ores
Rocks with enough metal in it that the cost of extracting it will be less than the money it can then be sold on for
What ores contain Aluminium Mercury Lead Iron Copper
Bauxite Cinnabar Galena Haematite Malachite
What is extraction
The process and removing metal from its ore using a chemical reaction
How are medium reactive metals extracted
If they are less reactive than carbon, they can be extracted by heating the ore with carbon, the carbon will displace the metal from its oxide ore to make pure metal and carbon dioxide
How do more reactive metals get extracted
The ore is heated till molten and the electrolysis is used to extract the metal into the pure metal on the cathode and the oxygen at the anode
What is reduction in core
Removal of oxygen from oxide compounds, such as extracting metals from their ores
What is the process of rusting called
Oxidation, the metal gains oxygen to become an oxide
Even though aluminium is quite reactive, why doesn’t it corrode fast
An oxide layer forms on fast and acts as a protective layer so the rest of the aluminium can’t oxidise
What are the advantages of recycling metal, 5
Natural reserves of metal ores will last longer
Recycling normally uses less energy than extraction from its ore so it’s cheaper
Reduces the need for mining so less noise and landscape damage
Less metals are disposed of in landfill sights
What are the disadvantages of recycling
Sometimes costs more to recycle than extract
Transport, collection and sorting takes time, energy and money
What percentage of aluminium, copper, lead and iron(steel) is recycled
Aluminium, 40
Copper, 30
Lead, 75
Iron(and steel), 40
What is an alloy
A mixture of metals, usually to share and improve characteristics
How can alloys inprove the strength of metals
Pure metals are very soft and malleable as all the atoms are the same size so move around quite easily, in alloys, the atoms are different shapes so it’s harder to move them around so it becomes stronger
What is nitinol and what’s so special about it
It is a smart material that remembers its shape. It can be crumpled and twisted but when it’s heated, it will return to its original shape.
