Question

a metal nitrate "A" on heating gives yellowish brown coloured metal oxide along with brown gas "B" and colourless gas "C".Aqueous solution of "A" on reacting with potassium iodide forms a yellowish precipitate of compound "D". identify "A" "B" "C" "D". identify both type of reaction. metal present in "A"is used in makeing paints

Answer 1

The metal nitrate (A) is Lead nitrate (Pb(NO₃)₂)
On heating it produces Lead oxide, Nitrogen dioxide (B) and oxygen gas (C)
          2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂
       Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃
then,A = (Pb(NO₃)₂)
                         B = NO₂
                         C = O₂
                         D = PbI + KNO₃ (mixture of compounds)

Answer 2

The metal nitrate (A) is Lead nitrate (Pb(NO₃)₂)

On heating it produces Lead oxide, Nitrogen dioxide (B) and oxygen gas (C)

         2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂

      Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃

then,A = (Pb(NO₃)₂)

                        B = NO₂

                        C = O₂

                        D = PbI + KNO₃ (mixture of compounds)