What is the solid residue in the thermal decomposition of lead nitrate?
Answer and explanation
Correct answer: Lead oxide
When lead nitrate is heated, it decomposes according to 2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂. Lead oxide, PbO, remains as the solid residue, while nitrogen dioxide and oxygen escape as gases. Lead sulphate, lead chloride, and lead carbonate are not products of this decomposition because their anions are absent from the reactant. Therefore, option A is correct.
Frequently asked questions
What is the correct answer to this question?
Lead oxide
Why is this the correct answer?
When lead nitrate is heated, it decomposes according to 2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂. Lead oxide, PbO, remains as the solid residue, while nitrogen dioxide and oxygen escape as gases. Lead sulphate, lead chloride, and lead carbonate are not products of this decomposition because their anions are absent from the reactant. Therefore, option A is correct.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
