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Let us do an activity to understand the process of decomposition.
Activity \(1.6\): Decomposition of lead nitrate.
  
Materials required:
  
-Lead nitrate powder \(2\)
-Boiling tube
-Tongs and
-Burner
  
Experimental procedure:
  
Step 1: Take \(2\) g white lead nitrate powder in a boiling tube.
Step 2: Heat the boiling tube over the flame of the burner using the tong.
Step 3: Observe what happens when you are heating lead nitrate in the boiling tube.
 
Observation:
  • Emission of brown fumes (brown fumes coming out of the test tube).
  • The white lead nitrate, after heating, converted into a brown powder.
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Decomposition of lead nitrate
  
Result:
  
The brown fumes coming out of the boiling tube are nitrogen dioxide.
The brown powder formed after heating the white lead nitrate is lead oxide.
 
Decomposition reaction:
  
\(2Pb(NO_3)_2\)(s) Heat \(2PbO\)(s) + \(4NO_2\)(g) + \(O_2\)(g)
(Lead nitrate)               (Lead oxide) + (Nitrogen dioxide) + (Oxygen)
  
Conclusion:
 
In this reaction, you can notice that a single reactant breaks down to give simpler products. This is known as a decomposition reaction. Here lead nitrate decomposes into lead oxide, nitrogen dioxide, and oxygen.