I really need help with this one. Finding solubility of Ca(OH)2 by titrating with 0.1 mol HCl. Ca(OH)2 mass is unknown. Initial pH in solution is 11.72, 100ml water. You need two H+ to neutralize one dissociated molecule of Ca(OH)2 as it has two OHs, but then you will have two H+ for every Ca molecule??

Also, its said Ca(OH)2 solubility is like 0.18 g / 100ml. But not all Cal. hydr. molecules dissociate even if you put just 0.18g for 100ml water, right?

Question

I really need help with this one. Finding solubility of Ca(OH)2 by titrating with 0.1 mol HCl. Ca(OH)2 mass is unknown. Initial pH in solution is 11.72, 100ml water. You need two H+ to neutralize one dissociated molecule of Ca(OH)2 as it has two OHs,  but then you will have two H+ for every Ca molecule??

Also, its said Ca(OH)2 solubility is like 0.18 g / 100ml. But not all Cal. hydr. molecules dissociate even if you put just 0.18g for 100ml water, right?