H2S is passed into one dm3 of a solution containing 0.1 mole of Zn2 and 0.01 mole of Cu2 till the sulphide ion concentration reaches 8.1 ´10–19 moles. Which one of the following statements is true? [Ksp of ZnS and CuS are 3]´ a Both CuS and ZnS precipitate b Only ZnS precipitates c No precipitation occurs d Only CuS precipitates Both CuS and ZnS precipitate

H2S is passed into one dm3 of a solution containing 0.1 mole of Zn2 a

1.	H2S is passed into one dm3 of a solution containing 0.1 mole of Zn2 and 0.01 mole of Cu2 till the sulphide ion concentration reaches 8.1 ´10–19 moles. Which one of the following statements is true? [Ksp of ZnS and CuS are 3]´ a Both CuS and ZnS precipitate b Only ZnS precipitates c No precipitation occurs d Only CuS precipitates Both CuS and ZnS precipitate
A.	Both CuS and ZnS precipitate
B.	Only ZnS precipitates
C.	No precipitation occurs
D.	Only CuS precipitates
Answer» B. Only ZnS precipitates