Yellow ammonium sulphide solution is a suitable reagent for the separation of

Options

A. HgS and PbS
B. PbS and `Bi_2S`
C. `Bi_(2)S_(3)` and `CuS`
D. `CdS and As_(2)S_(3)`

Answer

D

Explanation

`Cd^(+2)` belongs to II A group while `As^(+3)` to Iib.All the sulphides of II B are soluble in yellow ammonium sulphide but those of II A are insoluble.