The electrolysis of carbon dioxide gas, CO₂, in water is one way of making ethanol, C₂H₅OH - VCE - SSCE Chemistry - Question 2 - 2020 - Paper 1
Question 2
The electrolysis of carbon dioxide gas, CO₂, in water is one way of making ethanol, C₂H₅OH.
The diagram below shows a CO₂–H₂O electrolysis cell. The electrolyte use... show full transcript
Worked Solution & Example Answer:The electrolysis of carbon dioxide gas, CO₂, in water is one way of making ethanol, C₂H₅OH - VCE - SSCE Chemistry - Question 2 - 2020 - Paper 1
Step 1
Identify the Cu–Zn electrode as either the anode or the cathode in the box provided in the diagram above.
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Answer
The Cu–Zn electrode is identified as the cathode. In electrolysis, reduction occurs at the cathode, where the Cu-Zn electrode gains electrons during the reaction.
Step 2
Determine the applied voltage required for the electrolysis cell to operate.
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Answer
To ensure the electrolysis occurs, the applied voltage must be greater than the difference in standard electrode potentials, which in this case is calculated to be greater than 0.73 V.
Step 3
Write the balanced equation for the overall electrolysis reaction.
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Answer
The balanced overall reaction for the electrolysis can be written as:
