Neutral ferric chloride is added to the aqueous solution of acetate. $A$ blood-red colour is obtained; this is due to the formation of which compound?

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

The gas evolved when sodium sulfide is heated with dilute $HCl$ is:

Why is it necessary to use acetic acid and not sulphuric acid for acidification of sodium extract for testing sulphur by lead acetate test?

$A$ white crystalline salt $A$ reacts with dilute $HCl$ to liberate a suffocating gas $B$ and also forms a yellow precipitate. The gas $B$ turns potassium dichromate acidified with dilute $H_{2}SO_{4}$ to a green coloured solution $C$. $A$,$B$ and $C$ are respectively

Sodium salt solution $+ \, AgNO_3$ solution $\to$ Coloured precipitate: If the coloured precipitate is soluble in both dilute $HNO_3$ and excess concentrated $NH_3$ solution,then which of the following anions is present in the salt solution?