Assign $A, B, C, D$ from the given type of reaction.
$FeCl_3 + NH_3 \text{ (excess)} \longrightarrow Fe(OH)_3 \downarrow$

Which of the following pairs cannot be separated by passing $H_2S$ gas?

$A$ black sulphide is formed by the action of $H_2S$ on

$A$ compound is soluble in water. If ammonia is added,a red precipitate appears which is soluble in dilute $HCl$. The compound contains:

Which one of the following statements is correct?

Consider the following reaction scheme: $D(\text{White ppt}) \xleftarrow{Na_2CO_3} A \xrightarrow[\text{in acetic acid}]{K_2CrO_4} B(\text{Yellow ppt})$ and $A \xrightarrow{dil.\ H_2SO_4} C(\text{White ppt})$. If $A$ is a metallic salt,then the white precipitate $D$ must be: