$A$ salt gives violet vapours when treated with conc. $H_2SO_4$. It contains

Choose the correct matching:-

Column-$I$	Column-$II$
$(P) NaBr + \text{conc. } H_2SO_4 \rightarrow$	$(A) \text{Colourless gas}$
$(Q) Na_2S + \text{dil. } HCl \rightarrow$	$(B) \text{Brown colour}$
$(R) NaNO_2 + \text{dil. } HCl \rightarrow$	$(C) \text{Rotten smell}$
$(S) NaNO_3 + \text{conc. } H_2SO_4 \rightarrow$	$(D) \text{Paramagnetic}$

Which of the following silver precipitates dissolves in $dil. \, HNO_3$ to produce a clear solution?

Select the $CORRECT$ statement based on the following reactions:
$\text{Salt } 'X' (\text{soluble}) + \text{dil. } H_2SO_4 \to \text{gas } (B) + \text{neutral oxide } (C) + 'Y'$
$\text{Salt } 'X' (\text{soluble}) \xrightarrow{BaCl_2 \text{ solution}} \text{White ppt. } 'Z'$
$\text{aq. sol. of gas } (B) \xrightarrow{H_2S(g)} 'Y' + \text{neutral oxide } (C)$
Given these reactions,identify the correct statement regarding salt $'X'$.

$P_{(Coloured \ Solution)} + BaCl_2 \to Q \downarrow_{(White)} + R_{(Coloured \ Solution)}$
Then salt $P$ in above reaction is

During the qualitative analysis of $SO_{3}^{2-}$ using dilute $H_{2}SO_{4}$,$SO_{2}$ gas is evolved which turns $K_{2}Cr_{2}O_{7}$ solution (acidified with dilute $H_{2}SO_{4}$):