predict whether or not a precipitate will form if you mix 75ml of a NaOH solution with pOH = 2.58 with 125ml of a 0.018M MgCl2 solution. Identify the precipitate, if any.

Question

DrBob222 · Answer

(Mg^+2) = 0.018M x (125/200) = ??
pOH = 2.58 = -log(OH^-) and
(OH^-) = 0.00263 x (75/200) = ??
Qsp Mg(OH))2 = (Mg^+2)(OH^-)^2
Substitute the concns into Qsp and compare the result withe Ksp for Mg(OH)2. If Qsp > Ksp a ppt of Mg(OH)2 will form.