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प्रश्न
On heating blue coloured powder of copper (II) nitrate, in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed
- Write a balanced chemical equation of the reaction.
- Identify the brown gas X evolved.
- Identify the type of reaction.
- What could be the pH range of aqueous solution of the gas X?
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उत्तर
- `underset("Copper (II) nitrate")(2"Cu"("NO"_3)_2)("s") overset "(Heat)"(->) underset "(Black)" (2"CuO"("s")) + underset(X)(4"NO"_2("g")) + "O"_2("g")`
- Brown gas (X) is nitrogen dioxide.
- It is an example of decomposition reaction.
- Nitrogen dioxide is an acidic oxide. Therefore, it dissolves in water to form an acidic solution. The pH of the solution is expected to be less than 7.
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