Question

The cation that will not be precipitated by $H_{2}S$ in the presence of dilute $HCl$ is :

• A. $C{u}^{2+}$
• B. $P{b}^{2+}$
• C. $A{s}^{3+}$
• D. $C{o}^{2+}$

Answer 1

Answer: (A)

$C{u}^{2+},P{b}^{2+},A{s}^{3+}$ are all precipitated in Group II by $H_{2}S$ in the presence of $HCl.$

$C{o}^{2+}$ cannot be precipitated in group III