Misconception 1: "You can extract aluminium by heating with carbon"
Aluminium is more reactive than carbon, so carbon cannot reduce aluminium oxide. The carbon is not reactive enough to pull oxygen away from aluminium — electrolysis is required instead.
Misconception 2: "Cryolite is the ore of aluminium"
Cryolite is not the ore — bauxite (aluminium oxide, Al₂O₃) is the ore. Cryolite is added as a solvent to lower the melting point of aluminium oxide. Cryolite itself is now largely synthetic.
Misconception 3: "Oxidation means gaining oxygen, so the metal is oxidised during reduction"
The metal oxide is reduced (loses oxygen). The carbon or carbon monoxide is oxidised (gains oxygen). Students often confuse which substance is oxidised and which is reduced — remember: OIL RIG (Oxidation Is Loss, Reduction Is Gain — of electrons); or for oxygen: reduction = loss of oxygen.
This common misconceptions covers Common Misconceptions within Extracting Metals for GCSE Chemistry. Revise Extracting Metals in Chemical Changes for GCSE Chemistry with 6 exam-style questions and 6 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 10 of 14 in this topic. Use this common misconceptions to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Extracting Metals
Which method is used to extract a metal that is MORE reactive than carbon?
Iron is extracted from haematite in a blast furnace. Describe how iron is obtained from iron oxide using carbon, and explain the term 'reduction' in this context.