$A$ colourless crystalline salt $X$ is soluble in dilute $HCl$. On adding $NaOH$ solution,it gives a white precipitate which is insoluble in excess of $NaOH$. $X$ is

In the group $III$ radicals,in place of $NH_4Cl$,which of the following can be used?

$A$ salt '$A$' which gives a green flame with a Bunsen burner,on reaction with dil. $H_2SO_4$ produces gas $(2)$ and white turbidity $(Z)$. The saturated solution of gas $(2)$ on reaction with $H_2S$ gas produces '$Z$'. Then select the $CORRECT$ statement.

$A$ white crystalline substance dissolves in water. On passing $H_2S$ in this solution,a black precipitate is obtained. The black precipitate dissolves completely in hot $HNO_3$. On adding a few drops of conc. $H_2SO_4$ a white precipitate is obtained. This precipitate is that of:

An aqueous solution of a salt $X$ turns blood red on treatment with $CNS^{-}$ and blue on treatment with $K_4[Fe(CN)_6]$. $X$ also gives a positive chromyl chloride test. The salt $X$ is

$A$ precipitate of which of the following is obtained when $HCl$ is added to a solution of stannous sulphide $(SnS)$ in yellow ammonium sulphide?