Calculate pH at which `Mg(OH)_(2)` begins to precipitate from a solution containing `0.10M` `Mg^(2+)` ions. `(K_(sp)` of `Mg(OH)_(2)=1xx10^(-11))`

Explanation

Minimum `[OH^(-)]` after which `Mg (OH)_(2)` begins to precipitate can be calculated from
`[Mg^(2+)][OH^(-)]^(2)=K_(sp) ` of `Mg(OH)_(2)`
`(0.10)[OH^(-)]^(2) = 10^(-11) or [OH^(-)]^(2) = 10^(-10) or [OH^(-)]=10^(-5) or [H^(+)]=10^(-9) or pH = 9`