Question

Lead nitrate crystals on strong heating decompose to form lead monoxide, nitrogen dioxide and oxygen gas. Explain.

Answer 1

Hint : When two different types of element or compounds react with each other in specific atmospheric conditions they lead to the formation of various types of products. Lead nitrate is basic in nature and also participates in complex formation.
Source of energy is always required in the decomposition reaction to complete the reaction.

Complete Step By Step Answer:
In a decomposition reaction a single compound breaks to form many simpler products. Decomposition reaction carried out in the presence of any energy source to proceed the reaction in the form of heat, electricity or light.
Lead nitrate is a reactive inorganic compound which has the tendency to undergo various chemical reactions to form a product.
Lead nitrate undergoes a decomposition reaction in the presence of heat to produce simpler products.
When we treat lead nitrate over the heat it decomposes to produce mainly two products.
Final product of the decomposition reaction is lead monoxide, nitrogen dioxide and oxygen gas.
 $ {\left( {PbN{O_3}} \right)_{\left( S \right)}}\dfrac{\Delta }{{heat}}Pb{O_{\left( S \right)}} + N{O_2}_{\left( g \right)} + {O_2}_{\left( g \right)} $
In order to write the balanced chemical equation take two moles of lead nitrate which further form two moles of lead oxide, four moles of nitrogen gas and one mole of oxygen gas.
 $ {\left( {PbN{O_3}} \right)_{\left( S \right)}}\dfrac{\Delta }{{heat}}Pb{O_{\left( S \right)}} + N{O_2}_{\left( g \right)} + {O_2}_{\left( g \right)} $ $ 2{\left( {PbN{O_3}} \right)_{\left( S \right)}}\dfrac{\Delta }{{heat}}2Pb{O_{\left( S \right)}} + 4N{O_2}_{\left( g \right)} + {O_2}_{\left( g \right)} $
Above reaction is also used for the commercial preparation of lead oxide.

Note :
Lead nitrate also reacts with metal iodide to form precipitate. For example, when reacting with sodium iodide it forms lead iodide and sodium nitrate.
 $ {\left( {PbN{O_3}} \right)_2} + 2NaI \to Pb{I_2} + NaN{O_3} $
Lead nitrate is an inorganic compound which is commercially used widely to produce various pigments, in the leaching process for gold extraction.