# Chemistry - Ksp

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i did an experiment where we titrated HCl on calcium hydroxide, and now i am confused with the calculations, i do not know if i am correct, so please help me out...

Trial One
volume of HCl used - 11.20mL
concentration of HCl - 0.04mol/L
so to get moles of HCl i used M= CV
is that correct?

than to get moles of OH- in the solution, i did (M*V)/ 10mL(vlume of calcium hydroxide)
is that correct?

but then how do i find out the concentration of [OH-] and [Ca2+] at equilibrium. when i a supposed to even find out the Ksp int he same experiment?

• Chemistry - Ksp - ,

Your information is sketchy at best. For example, where did the 10 mL come from?
You don't know what you have if you don't write the equation of what's happening.
Ca(OH)2 + 2HCl ==> CaCl2 + 2H2O

moles HCl = M x L = ??
Using the coefficients in the balanced equation, convert moles HCl to moles Ca(OH)2. Therefore, moles Ca(OH)2 = 1/2 the moles HCl. Then since there are two OH^- in 1 molecule Ca(OH)2, there must be 2xmoles Ca(OH)2 = (OH^-).
So now you have Ca^2+ and OH^-, provided the 10 mL doesn't mess things around.