Question

A white salt on heating decomposes to give brown fumes and a residue is left behind. a) Name the salt b) Write the equation for the reaction.

Answer 1

Answer:

Explanation:

As on heating lead nitrate gives brown fumes of nitrogen dioxide gas. The liberation of brown gas indicates the presence of nitrate salt. The residue left behind must be lead (II) oxide that is yellow color residue. In this reaction, thermal / heating breaks the molecule therefore it is a thermal decomposition

Answer 2

Explanation:

The given white salt is lead nitrate Pb(NO3) 2

It decomposes to give brown fumes(NO2)

and yellow residue(PbO). The reaction can be given as follows:

2Pb(NO3) 2→2PbO+4NO 2+O2