Posted by LT on .
a solution saturated in calcium hydroxide(limewater) has a pH of 12.35. What is Ksp for calcium hydroxide?
How do i start this problem. please
Ca(OH)2 ==> Ca^+2 + 2OH^-
pH = 12.35
pOH = 14-12.35
Convert (OH^-) to (Ca^+2)
Calculate Ksp = (Ca^+2)(OH^-)^2
Post your work if you get stuck.
I follow you so far but how do you calculate OH
pOH = 1.65 = -log(OH^-).
Do you know how to solve that?
-log(OH^-) = 1.65
log(OH^-) = -1.65
Enter -1.65 in your calculator and hit the 10x key. Tht will give you 0.022387 31M. (That is more places than you can use but that's the number that shows up on my calculator.)