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

Which reagent is used to remove $SO_4^{2-}$ and $Cl^{-}$ ions from a solution?

The phosphate radical reacts with ammonium molybdate to form a precipitate of which color?

$A$ solution of a salt in dilute $H_2SO_4$ gives a blue color with starch iodide solution. This indicates the presence of which ion?

Aqueous solution of a salt $(A)$ forms a dense white precipitate with $BaCl_{2}$ solution. The precipitate dissolves in dilute $HCl$ to produce a gas $(B)$ which decolourises acidified $KMnO_{4}$ solution. $A$ and $B$ respectively are

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