Question

a white substance X is heated and brown colour fumes are evolved and a yellow substance is obtained write the name of X write down the chemical reaction and type of chemical reaction

Answer 1

Answer:

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+4NO2+O2

Answer 2

The name of the substance X is lead nitrate or Pb(NO3)2.

• When,the lead nitrate (white) is heated,three products are obtained.

1) Lead monoxide. (Yellow)

2) Nitrogen dioxide. (Brown)

3) Oxygen.

In this way,the products of this chemical reaction satisfies all the conditions given in the question.

• Chemical equation of the given chemical reaction :

2Pb(NO3)2 +∆ ---> 2PbO + 4NO2 + O2

• Here,the lead nitrate decomposes into lead monoxide, nitrogen dioxide and oxygen gas. So, it's a decomposition reaction.