On heating lead nitrate, brown fumes indicate the presence of which gas?
Answer and explanation
Correct answer: Nitrogen dioxide
Thermal decomposition of lead nitrate produces nitrogen dioxide, lead oxide, and oxygen: \(2\mathrm{Pb(NO_3)_2} \rightarrow 2\mathrm{PbO} + 4\mathrm{NO_2} + \mathrm{O_2}\). \(\mathrm{NO_2}\) is a brown gas, so the brown fumes indicate its presence. Oxygen is also formed, but it is colourless.
Frequently asked questions
What is the correct answer to this question?
Nitrogen dioxide
Why is this the correct answer?
Thermal decomposition of lead nitrate produces nitrogen dioxide, lead oxide, and oxygen: \(2\mathrm{Pb(NO_3)_2} \rightarrow 2\mathrm{PbO} + 4\mathrm{NO_2} + \mathrm{O_2}\). \(\mathrm{NO_2}\) is a brown gas, so the brown fumes indicate its presence. Oxygen is also formed, but it is colourless.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
