- Ore
- Rock containing enough metal compound to make extraction economically worthwhile.
- Reduction
- Loss of oxygen (or gain of electrons). Metal oxides are reduced during extraction to obtain the metal.
- Oxidation
- Gain of oxygen (or loss of electrons). The reducing agent is oxidised in the process.
- Electrolysis
- Breaking down a compound using electrical energy. Used for metals more reactive than carbon.
- Cryolite
- A compound added to aluminium oxide during electrolysis to lower its melting point, reducing energy costs.
- Bioleaching
- Using bacteria to extract metal compounds from low-grade ores.
- Phytomining
- Using plants that absorb metals from soil; plants are harvested and burned to obtain the metal from the ash.
This definitions covers Key Terms 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 8 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
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.
Quick recall flashcards
Which metals must be extracted by electrolysis, and why?
Metals MORE reactive than carbon (e.g. aluminium, sodium, potassium) must be extracted by electrolysis. Carbon is not reactive enough to pull oxygen away from them.
What is haematite, and where is iron extracted from it?
Haematite is iron oxide (Fe₂O₃) — the main ore of iron. Iron is extracted from haematite in a blast furnace using carbon (coke) as the reducing agent.