Hello. I have a question about a problem I'm solving. It says here a sample of serum was treated with KOH, added with a Cal-Red indicator, and finally with EDTA. Then, it asks for the level of Calcium in the serum. I understand that complexometric titrations are for metals except for the 1A/alkali metals. I've written the chemical reaction that I think happens.
Ca2+ + KOH ---> CaOH2 + K
At this point, I get confused. Will Ca(OH)2 react with EDTA? I've searched for this but the only results are calcium carbonate with EDTA.
The problem requires the levels of Ca in mg/dl and in meq/L. I've been solving this for hours but my answers are way big to be answers. I did not include the given numerical values. I am only after understanding what really happens in this kind of titration. Thank you!