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Question
Classify the following as chemical or physical change:
Passing of electric current through water, and water breaking down into hydrogen and oxygen gases.
Options
Chemical change
Physical change
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Solution
Chemical change
Explanation:
The passage of electric energy through water to form hydrogen and oxygen gases is a chemical change because the properties of hydrogen (a combustible gas) and oxygen (a supporter of combustion) are completely different from those of water, which is neither combustible nor a supporter of combustion but does extinguish the fire.
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