Passing `H_(2)S` gas into a mixture of `Mn^(2+) , Ni^(2+) , Cu^(2+)` and `Hg^(2+)` ions in an acidified aqueous solution precipitatates:

Options

A. `CuS` and `HgS`
B. `MnS` and `NiS`
C. `MnS` and `NiS`
D. `NiS` and `HgS`

Answer

A

Explanation

In presence of acidic medium, ionisation of `H_(2)S` is supressed to less number of `S^(2-)` ions are produces.So only those sulphides are precipitated which have low solubility product `(K_(sp))` value, For example `CuS` and `HgS`.