The group reagent $NH_4Cl_{(s)}$ and aqueous $NH_3$ will precipitate which of the following ions?

When $H_2S$ gas is passed through the $HCl$ containing aqueous solutions of $CuCl_2$,$HgCl_2$,$BiCl_3$ and $CoCl_2$,which does not precipitate out?

Statement-$1$: Few drops of $HNO_3$ are added before proceeding to $III^{rd}$ group.
Statement-$2$: For the oxidation of $Fe^{+2} \rightarrow Fe^{+3}$.

In the wet tests for identification of various cations by precipitation,which transition element cation does not belong to group $IV$ in qualitative inorganic analysis?

Given below are certain cations. Using inorganic qualitative analysis,arrange them in increasing group number from $0$ to $VI$.
$A$. $Al^{3+}$ $B$. $Cu^{2+}$ $C$. $Ba^{2+}$ $D$. $Co^{2+}$ $E$. $Mg^{2+}$
Choose the correct answer from the options given below.

Match List-$I$ with List-$II$ and select the correct answer using the codes given below.

List-$I$ (Ion involved)	List-$II$ (Agent)
$(i) \, Ni^{2+}$	$(A).$ Sodium thiosulphate
$(ii) \, Ag^{+}$	$(B).$ Sodium nitroprusside
$(iii) \, Cu^{2+}$	$(C).$ Ammonia
$(iv) \, S^{2-}$	$(D).$ Dimethylglyoxime