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how do you recognize the endpoint in an acid-base titration
If I remember my high school chemistry lab correctly, one uses a bit of special indicator mixed in with the solution. Phenolphthalein was the one we used which changes color from red to colorless when the pH goes from acid to base (maybe it was colorless to red, I don't remember everything). The web site http://en.wikipedia.org/wiki/PH_indicator
has a raft of different indicators for different ranges of pH changes.
(published on 03/29/2011)
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