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

Options

A. `2 xx 10^(-4) M`
B. `16 xx 10^(-4) M`
C. `8 xx 10^(-4) M`
D. `8 xx 10^(-8) M`

Answer

A

Explanation

`underset(S)(Ag_(2)CrO_(4)) rarr underset(2S)(2Ag^(+)) + underset(S)(CrO_(4)^(--))`
`K_(sp) = (2S)^(2)S = 4S^(3)`
`S = ((K_(sp))/(4))^((1)/(3)) = ((32 xx 10^(-12))/(4))^((1)/(3)) = 2 xx 10^(-4) M`.