, , and are Hg I 2 , K I , HgS and Hg respectively.

Sol. + → lilac colour in flame. So one of the cation may be K + .

+ black precipitate.

soluble Residue Greyish black precipitate .

+ brown precipitate. So second cation may be Hg 2+ .

(i) Sodium carbonate extract of salt violet colour.

(ii) Sodium extract of salt yellow precipitate soluble.

So the anion may be I – .

Hg I 2 + H 2 S HgS ↓ (black) + 2H I .

3HgS + 6HCl + 2HNO 3 3HgCl 2 + 2NO + 4H 2 O + S.

HgCl 2 + SnCl 2 Hg ↓ (greyish black) + SnCl 4 .

2K I + Hg I 2 K 2 [Hg I 4 ] (colourless).

2K 2 [Hg I 4 ] + NH 3 + 3KOH [HgOHg(NH 2 ) I ] ↓ ( brown).

Sodium carbonate extract of salt contains Na I .

2Na I + 2Fe 3+ I 2 (violet)+ 2Na + + 2Fe 2+ .

I 2 dissolves in CCl 4 giving violet colour solution.

AgNO 3 + Na I Ag I ↓ (yellow) + NaNO 3 .

Ag I is insoluble in ammonia solution.

So, , , and are Hg I 2 , K I , HgS and Hg respectively.