# The ion that cannot be precipitated by both HCl and $H_2S$ is

(a) $Pb^{2+}$
(b) $Cu^{2+}$
(c) $Ag^+$
(d) $Sn^{2+}$

Answer: $Cu^{2+}$

All except $Cu^{2+}$ are precipitated both with HCl and $H_2S$. $Cu^{2+}$ is not precipitated with HCl, it is precipitated only with $H_2S$.