which among the following pairs of ions cannot be separated by `H_(2)S` in the presence of dilute `HCl` ?

Options

A. `Bi^(3+) ,Sn^(4+)`
B. `Al^(3+) ,Hg^(2+)`
C. `Zn^(2+) ,Cu^(2+)`
D. `Ni^(2+) ,Cu^(2+)`

Answer

a

Explanation

In the presence of HCI both ions are precipitate by `H_(2)S`
`Bi^(3+) + H_(2)S overset(HCI) to underset(Brown)(Bi_(2)S_(3))darr `
`Sn^(4+) + H_(2)S overset(HCI) to underset(yellow)(SnS_(2) darr)