This question is about the electrolysis of aqueous solutions - AQA - GCSE Chemistry Combined Science - Question 5 - 2021 - Paper 1
Question 5
This question is about the electrolysis of aqueous solutions.
Hydrogen gas and chlorine gas are produced when sodium chloride solution is electrolysed.
Hydrogen io... show full transcript
Worked Solution & Example Answer:This question is about the electrolysis of aqueous solutions - AQA - GCSE Chemistry Combined Science - Question 5 - 2021 - Paper 1
Step 1
What type of reaction happens at the negative electrode? Give the reason for your answer.
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Answer
Type of reaction: Reduction
Reason: This is a reduction reaction because hydrogen ions (H+) gain electrons to form hydrogen gas (H2).
Step 2
Complete the half equation for the production of chlorine gas (Cl2).
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Answer
Cl- → Cl2 + 2e-
Step 3
Explain how oxygen gas is produced in the electrolysis of sodium sulfate solution.
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Answer
Oxygen gas is produced by the oxidation of water molecules. At the anode, water molecules are broken down to produce hydroxide ions (OH-), which are then oxidized, releasing oxygen gas (O2) as a byproduct.
