Solubility if `M_(2)S` type salt is `3.5xx10^(-6)`, then find out its solubility product

Options

A. `1.7xx10^(-6)`
B. `1.7xx10^(-16)`
C. `1.7xx10^(-18)`
D. `1.7xx10^(-12)`

Answer

B

Explanation

Solubility of `M_(2)S` salt is `3.5xx10^(-6)M`
`underset(3.5xx10^(-6)M)(M_(2)S)hArr underset(2xx3.5xx10^(-6)M)(2M^(+))+underset(3.5xx10^(-6)M)(S^(2-))` (on 100% ionisation)
`therefore K_(sp)` (solubility product of `M_(2)S`)
`=[M^(+)]^(2)[S^(2-)]`
`=(7.0xx10^(-6))^(2) (3.5xx10^(-6))`
`=171.5xx10^(-18)=1.71xx10^(-16)[M]^(3)`