The solubility product of `Ag CrO_(4)` is `32xx10^(-12).` What is the concentration of `CrO_(4)^(2-)` ions in that solution ?

Options

A. `2xx10^(-4)`
B. `16xx10^(-4)`
C. `8xx10^(-4)`
D. `12xx10^(-4)`

Answer

A

Explanation

`Ag_(2)CrO_(4)tounderset(2s)2Ag^(+)+underset(s)(CrO_(4)^(2-))`
`K_(sp)=[Ag^(+)]^(2)[CrO_(4)^(2-)]`
`=(2s)^(2)(s)`
`K_(sp)=4s^(3)`
`s=((K_(sp))/(4))^(1//3)`
`=((32xx10^(-12))/(4))^(1//3)=2xx10^(-4)M`