A colorless solid (A) when placed into water produces a heavy white turbidity to (B). Solid (A) gives a clear solution in conc.HCl when HCl solution is added to large amounts of water, (B) forms again. (B) dissolves in dilute HCl. When H2S is passed through a suspension of (A) or (B); a black precipitate (C) forms, (C) is insoluble in yellow ammonium sulphide (NH4)2S. Conc.H2SO4 added to solid (A) liberates gas (D). Gas(D) is water-soluble and gives white precipitate with mercuric salts (E) and not mercuric salts. The black precipitate (C) dissolves in HNO3 (1:1) to give a solution to which H2SO4 is added followed by addition of NH4OH when a white precipitate (F) is formed. (E) gives a black ppt. (G) with solution of sodium stannite.
When compound (A) reacts with
NH4OH, then product is a: