Who this is for: Cambridge IGCSE Coordinated Science (0654) students who want metal extraction — electrolysis, blast furnace and reduction with carbon — to become reliable marks instead of disconnected process diagrams.
What query it owns: how to understand and revise extraction of metals from their ores in Cambridge IGCSE Coordinated Science.
Why this is safe: this page owns the extraction-of-metals revision-guide angle, while Tutopiya’s Extraction Of Metals From Their Ores subtopic page owns the learning resource and the free Extraction Of Metals From Their Ores quiz owns the practice.

Most metals are found as compounds in ores and must be extracted. Cambridge IGCSE Coordinated Science (0654) expects you to explain why different methods are used — electrolysis for reactive metals, reduction with carbon for less reactive metals — and to describe the blast furnace extraction of iron and electrolysis of aluminium. This guide covers the syllabus processes, reactivity links and the question types that appear every year.

Key takeaways

• Unreactive metals (gold, silver) are found uncombined in the Earth.
• Metals above carbon in the reactivity series are extracted by electrolysis (e.g. aluminium from bauxite).
• Metals below carbon are extracted by reduction with carbon (e.g. iron in the blast furnace, zinc).
• In the blast furnace: iron ore (haematite) + coke + limestone → iron + slag; coke burns to CO which reduces Fe₂O₃.
• Bioleaching uses bacteria; phytomining uses plants to absorb metal ions — both are low-impact alternatives.

What is extraction of metals in Cambridge IGCSE Coordinated Science?

Metal extraction is the process of obtaining a pure metal from its ore. The method depends on reactivity — more reactive metals need a stronger reducing agent or electrical energy. Examiners test blast furnace equations, electrolysis of aluminium, the role of limestone, and why carbon cannot extract very reactive metals.

You can read the full explanation, diagrams and notes on Tutopiya’s Extraction Of Metals From Their Ores subtopic page before you attempt questions.

The core ideas you must master

Idea	What it means	How the exam uses it
Electrolysis	Electrical energy reduces molten ore	”Explain why aluminium is extracted by electrolysis.”
Reduction with carbon	CO or C removes oxygen from ore	”Describe the role of coke in the blast furnace.”
Blast furnace	Extracts iron from haematite	”Name the raw materials for the blast furnace.”
Slag formation	Limestone removes impurities	”Explain the role of limestone.”
Alternative methods	Bioleaching, phytomining	”Describe how bioleaching extracts copper.”

Extraction methods by reactivity

Metal	Ore (example)	Extraction method	Key detail
Aluminium (Al)	Bauxite (Al₂O₃)	Electrolysis of molten ore	Very reactive; carbon cannot reduce it
Iron (Fe)	Haematite (Fe₂O₃)	Blast furnace (C/CO reduction)	Coke → CO reduces iron oxide
Zinc (Zn)	Zinc blende (ZnS)	Roasting then C reduction	Below carbon in series
Copper (Cu)	Chalcopyrite / low-grade ore	Reduction or bioleaching	Can also be displaced from solution
Gold (Au)	Uncombined	Physical separation	Found native/uncombined

The blast furnace — step by step

The safest way to answer blast furnace questions is to follow the process in order.

1. Raw materials loaded: iron ore (haematite), coke (carbon), limestone.
2. Coke burns at the bottom → carbon dioxide formed (exothermic, provides heat).
3. CO₂ + C → 2CO — carbon monoxide is the reducing agent.
4. CO reduces iron oxide: Fe₂O₃ + 3CO → 2Fe + 3CO₂ — molten iron collects at the bottom.
5. Limestone (CaCO₃) decomposes → CaO; CaO reacts with sand (SiO₂) → slag (calcium silicate), which floats on the iron and is removed.
6. Molten iron is tapped off; slag used in road-building.

Test yourself with the Extraction Of Metals From Their Ores quiz once you can trace each step.

Extraction in past-paper wording: command words that matter

Command word / phrase	What the question wants	Typical extraction stem
Describe	Steps in a process	”Describe how iron is extracted in the blast furnace.”
Explain	Why a method is chosen	”Explain why aluminium cannot be extracted by carbon.”
State	Raw materials or products	”State the raw materials for the blast furnace.”
Write an equation	Balanced reduction equation	”Write the equation for the reduction of iron(III) oxide by CO.”
Compare	Two extraction methods	”Compare extraction of iron and aluminium.”

Worked exam-style stems (how to answer the wording)

1. “Explain why aluminium is extracted by electrolysis rather than by carbon.” Aluminium is above carbon in the reactivity series, so carbon cannot remove oxygen from aluminium oxide; electrolysis provides enough energy to reduce it. Mark-scheme reward: above carbon + carbon cannot reduce + electrolysis needed.
2. “State the role of limestone in the blast furnace.” Limestone decomposes to calcium oxide, which reacts with sand (silicon dioxide) to form slag that removes impurities. Reward: removes impurities/sand + forms slag.
3. “Describe how bioleaching is used to extract copper from low-grade ores.” Bacteria produce leachate that contains copper compounds; the copper is recovered from the leachate by displacement or electrolysis. Reward: bacteria + leachate + copper recovered.

How metal extraction connects to the rest of Coordinated Science chemistry

Extraction follows the Reactivity Series and links to Uses of Metals. The Cambridge IGCSE Coordinated Science resource hub links every Chemistry subtopic.

Common mistakes students make

• Stating carbon extracts aluminium (it cannot — aluminium needs electrolysis).
• Confusing coke (carbon), carbon monoxide (reducing agent) and carbon dioxide (product).
• Forgetting limestone forms slag (not iron).
• Describing electrolysis of aluminium without mentioning molten ore (solid does not conduct).
• Mixing up bioleaching (bacteria) with phytomining (plants).

When you need more support

If extraction questions keep costing marks, work through the Extraction Of Metals From Their Ores quiz, then get focused help from a Cambridge IGCSE Coordinated Science tutor.

Frequently asked questions

Why are different extraction methods used? Reactivity determines which reducing agent is strong enough — carbon works for iron but not for aluminium.

What is the role of carbon monoxide in the blast furnace? CO reduces iron(III) oxide to iron: Fe₂O₃ + 3CO → 2Fe + 3CO₂.

What is slag? Calcium silicate formed when calcium oxide reacts with sand; it removes impurities and floats on the molten iron.

How do I revise metal extraction effectively? Link each metal to its method via the reactivity series, learn blast furnace steps, then take the Extraction Of Metals quiz.

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