$Pb^{2+}$,$Cu^{2+}$,$Zn^{2+}$,and $Ni^{2+}$ ions are present in a given acidic solution. On passing hydrogen sulphide gas through this solution,the precipitate formed will contain:

Conc. $HNO_3$ is added before proceeding to test for group $III$ members. This is to

$A$ solution contains $Cl^{-}$,$I^{-}$,and $SO_{4}^{2-}$ ions. Which of the following ions is capable of precipitating all of the above when added to this solution?

$A$ solution prepared in conc. $HCl$ sometimes gives white turbidity even in the absence of $1^{st}$ group,when water is added to it. It is due to the presence of

When $H_2S$ gas is passed through a solution,it reacts to form a white precipitate. Which ion is present in the solution?

If $Pb^{2+}, Cu^{2+}, Al^{3+}, Cd^{2+}, Zn^{2+}$ radicals are present in an aqueous solution,and it reacts with $H^{+}/H_2S$,a precipitate is produced. The solution $(X)$ obtained after the removal of the precipitate is treated with excess $NaOH$. What is the result?