To an inorganic mixture,dilute $H_2SO_4$ is added in the cold; a colourless,odourless gas is evolved. The mixture contains:

$A$ substance reacts with dilute $H_2SO_4$ to release a colorless gas,which turns baryta water $[Ba(OH)_2]$ turbid and decolorizes an acidic solution of dichromate. The presence of which of the following is indicated by this reaction?

During the detection of an acidic radical present in a salt,a student obtains a pale yellow precipitate that is soluble with difficulty in $NH_4OH$ solution when the sodium carbonate extract is first acidified with dil. $HNO_3$ and then $AgNO_3$ solution is added. This indicates the presence of:

$M \text{ (Salt)} + \text{Dil. } HCl \xrightarrow{\text{Warm}} N \uparrow + P \downarrow$. Gas $N$ changes the colour of $FeSO_4$ solution into a yellow solution. Then,salt $M$ in the above reaction is:

Which of the following reagents would you use to separate $SO_4^{2-}$ ions from a solution containing a mixture of $SO_4^{2-}$ and $Cl^-$ ions?

When a few drops of $KMnO_4$ are added to an acidic solution of an anion,which of the following,if present,will $NOT$ decolorize $KMnO_4$?