Question

A metal nitrate $A$ on heating gives yellowish brown coloured metal oxide along with brown gas $B$ and colourless gas $C$.

Answer 1

Ans: The metal nitrate (A) is Lead nitrate$\left(Pb\right(NO₃\left)₂\right)$
On heating it produces Lead oxide, Nitrogen dioxide (B) and oxygen gas (C)
$2Pb\left(NO₃\right)₂\to 2PbO+4NO₂+O₂$
On reaction with potassium iodide mixture of lead iodide and potassium nitrate forms.
$Pb\left(NO₃\right)₂+2KI\to PbI₂+2KNO₃$

Alloy made of using lead is used in soldering purposes.
Therefore $A=\left(Pb\right(NO₃\left)₂\right)$
$B=NO₂$
$C=O₂$
$D=PbI+KNO₃$(mixture of compounds)