Copper Extraction Using Carbon
Materials: ★★☆ Available in most school laboratories or specialist stores
Difficulty: ★★☆ Can be done by science teachers
Safety: ★★☆ Some safety precautions required to perform safely
Categories: Oxidation and Reduction, Mining and Resources
Alternative titles: Reduction of Copper Oxide by Carbon
Summary
When a mixture of copper(II) oxide and carbon is heated, the carbon reduces the copper oxide to form copper metal and carbon dioxide gas. This reaction demonstrates how some metals are extracted from their ores.
Procedure
- Mix a small quantity of powdered copper(II) oxide with powdered carbon.
- Place the mixture in a heat-resistant test tube or crucible.
- Heat the mixture strongly using a Bunsen burner for several minutes.
- Observe the reaction as the black powder changes and metallic copper appears.
- Allow the products to cool and then examine them under a magnifying glass or microscope to identify small copper particles.
Links
Reduction of copper (II) oxide by carbon - Sergei's Chemistry:
Yr10 Copper oxide and carbon - WTN Chemistry Clips:
📄 Reactions between metals and metal oxides - Chemguide: https://www.chemguide.co.uk/14to16/rs/mandmo.html
Variations
- Use charcoal instead of pure carbon.
- Perform the reaction in a covered crucible and use a high-temperature Bunsen burner.
- Collect the gas released to confirm it is carbon dioxide.
Safety Precautions
- Safety glasses required.
- Heat-resistant gloves should be worn.
- Use tongs to handle hot test tubes or crucibles.
- Carry out the experiment in a well-ventilated area to avoid inhaling fumes.
- Ensure the carbon powder and copper oxide are handled carefully to avoid inhalation.
Questions to Consider
- Why can carbon reduce copper oxide but not reduce aluminum oxide? (Because aluminum is more reactive than carbon and cannot be displaced by it.)
- What evidence shows that a chemical reaction has occurred? (The appearance of copper metal and the release of carbon dioxide gas.)
- How does this experiment relate to the industrial extraction of metals? (It models the reduction of metal oxides using carbon in blast furnaces.)
- Why is heating necessary for this reaction? (The activation energy is high and heat provides the energy needed for the reaction to start.)