(i)A blue coloured compound `(A)` on heating gives two product `(B)` & `( C)`. (ii)A metal `(D)` is deposited on passing hydrogen through heated `(B)`. (iii)The solution of `(B)` in `HCl` on treatment with the `[Fe(CN)_(6)]^(4-)` gives a chocolate brown coloured precipitate of compound `(E)`. (iv)`(C )` turns lime water milky which disappears on continuous passage of `(C )` forming a compound `(F)`. Identigfy `(A)` to `(F)` and give chemical equations for the reactions at step (i) to (iv).
