Question

Calculate the [OH−] for 0.021 M Ca(OH)2. Answer in units of M.?

Answer 1

`0.042 \ "M"`

Explanation:

Well, we have a `0.021 \ "M"` solution of `Ca(OH)_2`.

Limewater will dissociate like the following equation:

`Ca(OH)_2rightleftharpoonsCa^(2+)+2OH^(-)`

So, one mole of limewater will contain two moles of hydroxide ions.

Therefore, in this solution of limewater, it has a total of `0.021 \ "M"*2=0.042 \ "M"` of hydroxide ions.