Where copper ore has been mined there are areas of land that contain very low percentages of copper compounds - AQA - GCSE Chemistry - Question 4 - 2014 - Paper 1
Question 4
Where copper ore has been mined there are areas of land that contain very low percentages of copper compounds.
One way to extract the copper is to grow plants on th... show full transcript
Worked Solution & Example Answer:Where copper ore has been mined there are areas of land that contain very low percentages of copper compounds - AQA - GCSE Chemistry - Question 4 - 2014 - Paper 1
Step 1
Complete the sentence.
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Answer
Using plants to extract metals is called phytomining.
Step 2
Suggest two reasons why copper from these areas of land is not extracted by smelting.
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Answer
The land contains very little copper, making it uneconomical to extract.
Smelting would allow for low-grade ore or result in large amounts of waste.
Step 3
Complete and balance the chemical equation for the reaction of copper oxide with carbon.
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The balanced equation is:
ightarrow 2 ext{Cu} + ext{CO}_2$$
Step 4
Give two reasons why scrap iron is used to displace copper.
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Iron is more reactive than copper, allowing it to displace copper from copper sulfate solution.
Using iron is more economical as it requires less energy than electrolysis.
Step 5
Describe what happens to the copper ions during electrolysis.
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Copper ions (extCu2+) move towards the negative electrode (cathode), where they are reduced to form copper metal. At the cathode, the reaction is:
