Extraction of metals

• Ores are rocks that contain a lot of metal elements, like hematite rich in iron and bauxite rich in aluminium

  
• Most metals, like iron and aluminium, are too reactive to be found in their metallic state but are instead trapped as ions in ionic compounds in ores
• The ease of obtaining metals from their ores is related to their position in the reactivity series; the more reactive a metal is, the harder it is to extract
• Iron is extracted from hematite in a blast furnace, while aluminium is extracted from bauxite using electrolysis
• In the blast furnace process for extracting iron, carbon + oxygen → carbon dioxide, carbon dioxide + carbon → carbon monoxide, iron(III) oxide + carbon monoxide → iron + carbon dioxide
• The blast furnace process also involves calcium carbonate → calcium oxide + carbon dioxide, and calcium oxide + silicon dioxide → calcium silicate (slag)
• The blast furnace process is used to produce iron from iron ore

  
• Aluminium is extracted from bauxite through the Hall-Héroult process, which involves electrolysis

  
• In the electrolysis of aluminum, at the cathode (negative electrode) aluminium ions gain electrons (reduction) to form molten aluminium, while at the anode (positive electrode) oxide ions lose electrons (oxidation) to produce oxygen
• During the electrolysis of aluminum, the carbon in the graphite anodes reacts with the oxygen produced to produce CO2, leading to the regular replacement of the carbon anodes