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Question
Differentiate between the following:
Electrolytic decomposition and photochemical decomposition.
Solution
- Electrolytic decomposition: “A decomposition reaction which is brought about by the passage of electric current.”
- Photochemical decomposition: “A decomposition reaction which takes place in presence of light.”
e.g. decomposition of silver salts in the presence of sunlight.
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- Take a plastic mug. Drill two holes at its base and fit rubber stoppers in these holes. Insert carbon electrodes in these rubber stoppers as shown in the following Fig.
- Connect these electrodes to a 6 volt battery.
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Caution: This step must be performed carefully by the teacher.
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