H_(2)S gas is passed into one dm^(3) of a solution containing 0.1 mole of Zn^(2+) and 0.01 mole of Cu^(2+) till the sulphide ion concentration reaches 8.1xx10^(-19) moles. Which one of the following statements is true ? (K_(sp) of ZnS and CuS are 3xx10^(-22) and 8xx10^(-36) respectively)

H_(2)S gas is passed into one dm^(3) of a solution containing 0.1 mole

1.	H_(2)S gas is passed into one dm^(3) of a solution containing 0.1 mole of Zn^(2+) and 0.01 mole of Cu^(2+) till the sulphide ion concentration reaches 8.1xx10^(-19) moles. Which one of the following statements is true ? (K_(sp) of ZnS and CuS are 3xx10^(-22) and 8xx10^(-36) respectively)
Answer» Only ZnS precipitates Both CUS and ZnS precipitate Only CuS precipitates No PRECIPITATION occurs Solution :Precipitation occursif ionic product `GT K_(sp)` Ionic product of `ZnS=[ZN^(2+)][S^(2-)]` `=0.1xx8.1xx10^(-19)=8.1xx10^(-20) gt K_(sp)` Ionic product of CuS `=[cu^(2+)][S^(2-)]` `=0.01xx8.1xx10^(-19)=8.1xx10^(-21) gt K_(sp)` Hence, both will precipitate.