When solid lead nitrate is heated in a test tube, what is not observed during the reaction is:
a)a cracking sound is produced
b)a brown gas is produced
c)a light yellow substance is formed
d)a brown precipitate is formed
The correct answer is (d) A brow precipitate is produced.
The decomposition of lead nitrate is given as per the following equation
2Pb(NO3)2 (s) → 2PbO (s) + 4NO2 (g) + O2 (g)
This is accompanied by a crackling sound. Also it releases nitrogen dioxide which is a brown coloured gas. The residue that is left behind that is PbO, is yellow in colour.