A compound is treated with NaNH2 to give sodium salt. Identify the compound.
An aqueous solution of a salt (A) gives white precipitate (B) with sodium chloride solution. The filtrate gives a black precipitate. (C) When H2S is passed into it. Compound (B) dissolves in hot water and the solution gives a yellow precipitate (D) on treatment with sodium iodide. The compound (A) does not give any gas with dilute HCl but liberates a reddish brown gas on heating. Identify the compound (A) to (D).