We just did a lab on Titration of H3PO4, to experimentally find pKa1 and pKa2 from the 2 endpoints found on the sigmoid curve. I understand all of that, but one of our discussion questions says: "Why were you not able to experimentally determine endpoint #3 and pKa3 in this experiment? What went wrong? "
I didn't think anything went wrong, so this is odd. I did however find a sentence in the lab intro that says "only 2 endopoints will be visible because of limitations in the measurement...."
Is this the reason? It doesn't make much sense.
Any ideas?

Question

We just did a lab on Titration of H3PO4, to experimentally find pKa1 and pKa2 from the 2 endpoints found on the sigmoid curve. I understand all of that, but one of our discussion questions says: "Why were you not able to experimentally determine endpoint #3 and pKa3 in this experiment? What went wrong? "
I didn't think anything went wrong, so this is odd. I did however find a sentence in the lab intro that says "only 2 endopoints will be visible because of limitations in the measurement...."
Is this the reason? It doesn't make much sense. 
Any ideas?

jotopia34 · Answer

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