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Question
The white solid compound A decomposes quite rapidly on heating in the presence of a black substance X to form a solid compound B and a gas C. When an aqueous solution of compound B is reacted with silver nitrate solution, then a white precipitate of silver chloride is obtained along with potassium nitrate solution. Gas C does not burn itself but helps burn other things.
- What is compound A?
- What is compound B?
- What is gas C?
- What do you think is the black substance X? What is its function?
- What is the general name of substances like X?
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Solution
- Compound A is potassium chlorate (KClO3).
- Compound B is potassium chloride (KCl).
- Gas C is oxygen gas (O2), which does not burn itself but helps burn other things.
- Black substance X is manganese oxide (MnO2). Its function is to catalyse the reaction.
- The general name of a substance like X (MnO2) is a catalyst.
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