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Topic: Titrating Weak Acid with Strong Base  (Read 3112 times)

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Offline shoofy2

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Titrating Weak Acid with Strong Base
« on: August 24, 2009, 02:47:11 PM »
Once again, my chemistry texts failed to provide a satisfactory answer to my dilemma:

When titrating a weak acid with a strong base, I know that the pH at the equivalence point will be higher than pH 7, since the strong base releases all its OH- ions while the weak acid only disassociates partially. But here is my problem: wouldn't the OH- and H+ form water, and thus, by Le Chatelier's Principle, cause the weak acid to push out even more H+ ions? Eventually, the OH- would "draw out" all the H+ from the weak acid, thus giving a neutral equivalence point.

What's wrong here?

Thanks for your time.
 

Offline Borek

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Re: Titrating Weak Acid with Strong Base
« Reply #1 on: August 24, 2009, 03:15:19 PM »
At the equivalence point you have a solution of salt of a weak acid. Anion is a conjugate base and will react with water.
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