Pb^{2+},Cu^{2+},Zn^{2+},and Ni^{2+} ions are | vedclass

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(B) In an acidic medium,the concentration of $S^{2-}$ ions is very low due to the common ion effect of $H^+$ ions from $HCl$ on the dissociation of $H

Vedclass · Accepted Answer

$PbS$ and $CuS$

Vedclass · Answer

(B) In an acidic medium,the concentration of $S^{2-}$ ions is very low due to the common ion effect of $H^+$ ions from $HCl$ on the dissociation of $H_2S$.$Pb^{2+}$ and $Cu^{2+}$ belong to Group-$II$ of the qualitative analysis scheme,which are precipitated as sulphides in an acidic medium because their solubility products $(K_{sp})$ are very low.$Zn^{2+}$ and $Ni^{2+}$ belong to later groups (Group-$III$ and $IV$) and require a higher concentration of $S^{2-}$ ions for precipitation,which is not achieved in an acidic medium.Therefore,only $PbS$ and $CuS$ will precipitate.Thus,the correct option is $(B)$.

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

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Which one of the following statements is correct?

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Choose the correct answer from the options given below $ : $

An aqueous solution contains the ions as $Hg_2^{2+}$,$Hg^{2+}$,$Pb^{2+}$,and $Cd^{2+}$. The addition of dilute $HCl$ $(6 \ N)$ precipitates:

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