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

Options

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

Answer

A

Explanation

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