When lead nitrate powder is heated in a boiling tube, we observe :
(a) Brown fumes of nitrogen dioxide
(b) Brown fumes of lead oxide
(c) Yellow fumes of nitrogen dioxide
(d) Brown fumes of nitric oxide
1 Answers
Correct answer is (a) Brown fumes of nitrogen dioxide
\(2 pb (NO_3)_2\) \(\overset{\text{heat}}{\longrightarrow}\) \(\underset{\text{Light yellow}}{2pbO↑} + \underset{\text{Reddish-Brown}}{4NO2↑}\) \(+ \underset{\text{colourless}}{O_2\uparrow}\)
Hence, The brown fumes will be nitrogen dioxide.
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