When $BaCl_{2}$ is added to an aqueous salt solution, a white precipitate is obtained. The anion among $CO_{3}^{2-}$, $SO_{3}^{2-}$, and $SO_{4}^{2-}$ that was present in the solution can be

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

An aqueous solution of a salt,when treated with $AgNO_3$ solution,gives a white precipitate which dissolves in $NH_4OH$. The radical present in the salt is:

Formation of $Na_4[Fe(CN)_5NOS]$,a purple coloured complex formed by addition of sodium nitroprusside in sodium carbonate extract of salt indicates the presence of $:$

In salt analysis,$Cl^{-}$,$Br^{-}$,and $I^{-}$ are identified by adding dilute $HNO_3$ followed by $AgNO_3$ solution to the salt solution. Choose the correct statements from the following:
$A$. $Cl^{-}$ gives pale yellow precipitate.
$B$. $Br^{-}$ gives pale yellow precipitate which is partially soluble in $NH_4OH$.
$C$. $I^{-}$ gives yellow precipitate which is insoluble in $NH_4OH$.
$D$. $Cl^{-}$ gives white precipitate which is soluble in $NH_4OH$.
$E$. $I^{-}$ gives yellow precipitate which is insoluble in $NH_4OH$.
Choose the correct answer from the options given below $:-$

In the brown ring test,the brown color for $NO_2^-$ and $NO_3^-$ is due to the formation of which complex ion?