c6.1 part 2 Flashcards
ore
rock/mineral that contains enough metal to make it ECONOMICAL to extract the metal
Ore extraction process
- mined
- processed to separate the metal compound from the ore
- extracted using chem reactions depending on POSITION in REACTIVITY series
Why are not all metals extracted using electrolysis?
Electricity is expensive SO
if metal is less reactive than carbon, cheaper methods are used (displacement reactions kind of)
How can copper and iron be extracted?
Heating compounds w CARBON or CARBON MONOXIDE
How is copper extracted from COPPER SULFIDE
Stage 1:
2CuS + O2 –>CuO + SO2
Stage 2
2CuO + C –> 2Cu + CO2
methods to extract copper from copper oxide
- crucible method w charcoal + cu0 powder
- or hear w methane/hydrogen to reduce to copper
How is iron extracted
Blast furnace
- w iron ore, coke(mostly carbon) and limestone
Stage 1 - Iron Extracting
C + O2 –> CO2
Coke burns in air to form carbon dioxide
Stage 2 - Iron extracting
C + CO2 –> 2CO(g)
More coke reduces carbon dioxide to carbon monoxide
Stage 3 - Iron extracting
3CO + Fe2O3(s) –> 3CO2 + 2Fe(I)
Carbon monoxide reduces iron(III) oxide to iron at 1500
Why does iron have to be purified
As the molten iron contains sandy impurities from the iron ore
How is iron purified generally
Impurities removed using the limestone - mostly calcium carbonate
Iron purification equations
- CaCO3 –> CaO + CO2
Calcium carbonate decomposes in the high temp - CaO + SiO2 –> CaSiO3
Calcium oxide formed reacts w silica from sandy impurities to form calcium silicate = slag
How is aluminium extracted and why (basic)
More reactive than carbon so extracted from ore(bauxite = aluminium oxide found)) by electrolysis
Aluminium oxide does not dissolve in water and m.p. is too high so how is it made liquid?
Aluminium oxide DISSOLVED in molten cryolite = much lower m.p. than aluminium oxide
= electrolysis can happen at 950 as opposed to 2000
