Question

What happens when
Lead nitrate solution treated with calcium chloride solution and products are heated and cooled.

Answer 1

When lead nitrate solution is treated with calcium chloride solution it forms white ppt. of lead chloride and calcium nitrate
CaCl_2(s) → Ca²⁺_(aq) + Cl^-_(aq)
\[\ce{Pb(NO3)2(aq) -> Pb^{2+}(aq) + NO^{2-}_{3}(aq)}\]

\[\ce{Pb^{2+}(aq) + NO^{2-}_{3}(aq) + Ca^{2+}(aq) + Cl-(aq) -> PbCl2 + Ca(NO3)2}\]

On further heating and cooling the products, calcium nitrate decomposes upon heating to release nitrogen dioxide:
2Ca(NO₃)₂ → 2CaO + 4NO₂ + O₂