Calculate `pH` of saturated solution `Mg(OH)_(2),K_(sp)` for `Mg(OH)_(2)` is `8.9 xx 10^(-12)`.

Explanation

Let solubility of `Mg(OH)_(2)` be `S mol L^(-1)`
`{:(Mg(OH)_(2)hArr,Mg^(2+)+,2overset(Θ)OH,,),(,S,2S,,):}`
`:. [Mg^(2+)] [overset(Θ)OH]^(2) = K_(sp)`
`4s^(2) = 8.9 xx 10^(-12) :. S = 1.305 xx 10^(-4)M`
`:. [overset(Θ)OH] = 2xx 1.305 xx 10^(-4)M`
`:. pOH = 3.5832` and `pH = 10.4168`