Ferric ion forms a Prussian blue coloured precipitate due to the formation of:

$PCl_5$ reacts with finely divided silver on heating and a white silver salt is obtained,which dissolves on adding excess aqueous $NH_3$ solution. Write the reactions involved to explain what happens.

Which ligand is used for the treatment of lead poisoning?

Prussian blue is due to the formation of

When potassium ferrocyanide crystals are heated with concentrated $H_2SO_4$,which of the following gases is evolved?

Identify $(A)$ to $(E)$ and also explain the reactions involved.
$CuCO_3 \to CuO$ $\xrightarrow{\text{Heat with } CuS} (A)$ $\xrightarrow{\text{conc. } HNO_3} (B)$ $\xrightarrow{NH_{3(aq)}} (C) \text{ (Blue solution)}$
$CuCO_3 \to (D)$ $\xrightarrow{Ca(OH)_2} (E) \text{ (Milky)}$ $\xrightarrow{CO_2} Ca(HCO_3)_2 \text{ (Clear solution)}$