Two gram of lead nitrate powder is taken in a boiling tube.The boiling tube is heated over a flame. Now answers the following.
(I) state the colour of the fumes evolved and the residue left.
(2) Name the type of chemical reaction that has taken place and state it's balance equation.
Answers
Explanation:
State of the color of the fumes evolved and the residue left:
The colorless lead (II) nitrate crystals upon heating undergoes thermal decomposition and forms a yellow solid precipitate of lead oxide and evolves "reddish brown fumes" of nitrogen dioxide gas.
Chemical reactions:
Upon heating lead nitrate strongly, it decomposes with a crackling sound and a precipitate of lead oxide is formed along with the release of oxygen and nitrogen dioxide gas.
The oxygen liberated can be tested by introducing a glowing splint near the boiling tube. The nitrogen dioxide gas produced is acidic and turns blue litmus paper red.
Balanced equation: 2 P b\left(N O_{3}\right)_{2} \rightarrow 2 \mathrm{PbO}(\mathrm{s})+\mathrm{NO}_{2}+\mathrm{O}_{2}2Pb(NO
3
)
2
→2PbO(s)+NO
2
+O
2
Answer:
1 NO2 gas is evolved which has reddish brown fumes
2) 2 Pb(NO3)2 ----> 2PbO ppt + 4NO2 (g)+ O2
Decomposition reaction