Obtaining and Using Metals Flashcards
What can you react metals with to find their reactivity?
Water and acid
What is the order of metals in the reactivity series + carbon and hydrogen?
Potassium, sodium, calcium, magnesium, aluminium, carbon, zinc, iron, tin, lead, hydrogen, copper, silver, gold, platinum.
What is an ore?
An ore is a naturally occurring rock, found in the Earth’s crust, which contains a metal or a metal compound in a high enough quantity to make it worthwhile to extract it.
What are the main ores of iron and aluminium?
Haematite and bauxite.
What is a displacement reaction?
A displacement reaction is when an element is added to a compound of elements. If the element added is more reactive than the one in the compound, the element will displace the one in the compound.
What happens in a blast furnace?
Iron ore, coke and limestone are put into the furnace, and coke displaces oxygen from the iron oxide, while limestone removes acidic impurities from iron by reacting to form slag.
What are the main reactions in a blast furnace?
2Fe2O3 + 3C –> 4Fe + 3CO2
2C + O2 –> 2CO
Fe2O3 + 3CO –> 2Fe + 3CO2
What happens in electrolysis?
A molten ore is poured into a steel case with a catalyst to reduce is melting point. There is a negative graphite cathode at the bottom of the case, and positive anodes at the top. The positive metal is attracted to the negative cathode, which can easily be removed as a pure metal.
What are the problems with traditional mining?
It produces large amounts of waste rock, requires lots of energy, creates large holes in the Earth’s crust and is only worthwhile with high grade ores
What is the process of phytomining?
Plants are plante in soil with a high percentage of copper.
As the plant grows, its roots will absorb copper ions.
The plant is burnt in an oxygen rich environment, producing wast CO2.
Copper ions in the plant react with oxygen in the atmosphere to form copper oxide.
Electrolysis is used to obtain pure copper.
What are the advantages and disadvantages of phytomining?
It can use low grade copper ore, it requires less energy than smelting, it produces less air pollution and it reduces the amount of waste rock.
It can produce toxic chemicals, it is a much slower process and electrolysis requires a large amount of energy.
What is oxidation and reduction?
Oxidation is the gain of oxygen or loss of electrons, reduction is the loss of oxygen or gain of electrons.
Why does salt water increase the rate of corrosion?
Salt water is an electrolyte which conducts ions, which speeds up rusting because iron oxide is an ionic compound.
What are the benefits of recycling metals?
It uses up to 95% less electricity, it is cheaper than extracting and it creates less waste and reduces the number of sites that have to be mined.
How is aluminium recycled?
Aluminium is first sorted and cleaned. Then it is melted to remove inks. Then it is put into iron ingots, which are rolled out so that it can be used again.
