Extraction of Metals Flashcards
Ore of zinc?
Zinc Blende (ZnS)
Ore of aluminium
Bauxite (Al2O3)
Ore of iron
Hematite (Fe2O3
Raw materials of a blast furnace:
- haematite
- coke
- limestone (CaCO3)
Why is coke used in a blast furnace?
To produce CO to reduce the iron ore
Describe the process in a blast furnace
- Coke burns in the hot air to produce CO2
- CO2 is reduced to CO
- CO reduces haematite to iron
- Limestone undergoes thermal decomposition, producing CaO and CO2
- CaO combined with SiO2 (sand) to form CaSiO3 (calcium silicate)
Describe the extraction process of zinc
- Zinc blende is heated strongly in the presence of oxygen to convert zinc sulphide to zinc oxide
- Zinc oxide is reduced with carbon
Common forms of metal found naturally?
Metal carbonates/sulphides/oxides
What does the anode typically produce?
Nonmetals, or oxygen
What does the cathode typically produce?
Metals, or hydrogen
What happens during electrolysis?
- A direct current passes through the electrolyte
2. Electrical energy is changed to chemical energy
[cathode] ease of discharge chart
Fluorine Sulphate Nitrate Chlorine Bromine Iodine Hydroxide
Common inert electrodes:
- carbon
- platinum
Common active electrodes:
Copper, silver
How are results different with concentrated electrolytes?
Concentrated ions tend to crowd out other ions, and so obtain preference for discharge.