The solubility product of a salt having general formula `MX_(2)` in water is `4xx10^(-12)`. The concentration of `M^(2+) ions` in the aqueous solution of the salt is:

Options

A. `1xx 10^(-4) M`
B. `4 xx 10^(4) M`
C. `16 xx 10^(-6) M`
D. `2xx 10^(-4) M`

Answer

A

Explanation

`underset(S)(MX_(2)) hArr underset(S)(M^(2+)) +underset(2S)(2X^(-))`
`K_(sp) =[M^(2+)][X^(-)]^(2)`
`=S(2S)^(2)`
`=4S^(3) =4S^(3)`
`S=3sqrt((K_(sp))/(4))=3sqrt((4xx10^(-2))/(4))=1xx 10^(-4)M`