[kddk]

I have recently done a titration lab, and I'm having some trouble figuring out what will happen to the Ksp value of Calcium Hydroxide.

We were to use potassium hydrogen phthalate and calcium hydroxide. This is the equation I got:

2C8H5KO4 (aq) + Ca(OH)₂ (aq) 2H₂O (l) + Ca(C8H4KO4)₂ (aq)

The question for the lab is "What is the Ksp of Calcium Hydroxide at room temperate?"

I have the calculations completed, but I'm having some trouble structuring the hypothesis. I was thinking that since C8H5KO4 is present, then the equilibrium will shift either left or right (this is where I am stuck), and will alter the concentration of hydroxide ions, and the Ksp value in some way. Is this the right hypothesis for this type of lab?

The Ksp value came out to be higher, so I assume that the equilibrium must have shifted left. <--- Not sure about this though.

Any ideas?

Thanks in advance.

[Borek]

Please describe the procedure used. KHP in acid-base titration is used for solution standardization, so while it is possible it was used in some other way, I would prefer to know for sure what is going on.