Question 4 (higher question) Electrolysis of acidified water can produce hydrogen and oxygen.
The apparatus for the electrolysis is:
. water containing some dilute sulfuric acid
• two graphite rods
• a suitable container for the electrolysis reaction
. a suitable source of electricity
• test tubes
Describe how to use the apparatus to electrolyse acidified water, and how to test the gases to
show that they are hydrogen and oxygen. Include a diagram in your answer. [6 marks]

Explanation:

Describe means you should recall facts, events or processes accurately. You might need to give an account of what something looked like, or what happened.

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Compare means you need to describe similarities and differences between things. If you are asked to compare X and Y, write down something about X and something about Y, and give a comparison. Do not just write about X only or Y only.

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