Nessler's reagent is used to detect

$A$ reagent used to test the presence of $Fe^{2+}$ ion is

The $V^{-}A$ group precipitate was dissolved in $HNO_3$ and treated with an excess of $NH_4OH$. It gives a white precipitate because of:

Among $Fe^{3+}$, $Pb^{2+}$, $Cu^{2+}$, and $Mn^{2+}$, identify the one that gets precipitated out while passing $H_2S$ gas in the presence of $NH_4OH$ as a group reagent. The highest possible oxidation state of the corresponding metal is:

Which ions can be separated using concentrated $NaOH$?

Yellow ammonium sulphide solution is a suitable reagent for the separation of