We did not use the volume of the water added initially to the Erlenmeyer in our calculations. Why?
3 answers
Why do you think anything to do with the water is needed? It contains no moles of acid. It contains no moles of base. You are titrating acid with a base (or the other way around perhaps) and moles acid versus moles base is the only thing that matters, assuming the end point occurs where you want it to occur. My students always said to me, "but the water dilutes the stuff in the Erlenmeyer flask." And my response always was, "that is true but doesn't it dilute stuff added from the buret, also, and by the same amount?" Of course it does. The dilution explanation they usually understood, and it is true, but the REAL reason is what I wrote at the top of this discussion. The indicator knows where to change color in the acid/base relationship and the water has nothing to do with it except to give some volume to swish around in the flask.
Describe the apparent relationship between [H3O+1] and [OH-1] when the endpoint is reached in an acid-base
titiration.
titiration.
When the endpoint is reached in an acid-base titration the apparent relationship between [H3O+] AND [OH-] they are equal.
3 answers