Compound (A) is a greenish crystalline salt which gives the following results when tested :
(a) Addition of BaCl2 solution to a solution of (A) results in the formation of a white precipitate (B) which is insoluble in dilute HCl.
(b) On heating, water vapour and two gases (C) and (D) are liberated, leaving a red brown residue (E).
(c) (E) dissolves in conc.HCl to give a yellow solution (F).
(d) With H2S, the solution (F) yields a yellow-white ppt. (G) which when filtrated, leaves a greenish filtrate (H).
(e) The solution (F) gives a green solution with SnCl2, and when reacted with K4[Fe(CN)6] gives a blue ppt.
Identify compound (A) :