3 (a) Use words from the box to complete the sentences - Edexcel - GCSE Chemistry - Question 3 - 2013 - Paper 1
Question 3
3 (a) Use words from the box to complete the sentences.
(i) Iron is extracted from its ore by heating the ore with ____________________.
(ii) It is difficult to re... show full transcript
Worked Solution & Example Answer:3 (a) Use words from the box to complete the sentences - Edexcel - GCSE Chemistry - Question 3 - 2013 - Paper 1
Step 1
Use words from the box to complete the sentences.
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Answer
(i) Iron is extracted from its ore by heating the ore with carbon.
(ii) It is difficult to reduce aluminium ore to aluminium metal. Therefore, to produce aluminium from its ore, it is necessary to use electricity.
Step 2
Explain how this equation shows that lead oxide is reduced and carbon is oxidised.
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Answer
In the reaction:
lead oxide + carbon → lead + carbon dioxide,
lead oxide is reduced as it loses oxygen, transforming into lead. Conversely, carbon is oxidised as it gains oxygen from lead oxide to form carbon dioxide.
Step 3
Use the information from the table to explain why aluminium, rather than copper, is used for overhead power cables.
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Answer
Aluminium is preferred for overhead power cables because it is a good conductor of electricity, similar to copper, but it has a lower density. This means that aluminium cables are lighter than copper cables, making them easier to support and install over long distances.
Step 4
Complete the sentence by putting a cross (X) in the box next to your answer.
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Answer
Stainless steel is used instead of pure iron because it is D more resistant to corrosion.
Step 5
Use the graph to find the percentage of tin in the mixture that has the lowest melting temperature.
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Answer
The graph indicates that the lowest melting temperature occurs at 60% tin in the mixture.
Step 6
Describe how the melting temperature changes as the percentage by mass of tin in the mixture increases.
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Answer
As the percentage by mass of tin in the mixture increases, the melting temperature initially decreases to a minimum point and then begins to increase. This indicates that there is an optimal proportion of tin in the mixture that results in the lowest melting point.
