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I have HCl and NaOH titration and in the equivalence point I get pH=8.6, but the pH must be 7 in this kind of titration, then why this happen? Does it possible that I don't take enough points in the area of the equivalence point and this makes the pH>7?

maryam
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    Please look at the second graph here and also note that titration end point is not necessarily the same as equivalence point for an indicator. – Ed V Jun 11 '21 at 18:00

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The PH at equivalence point of titration for a strong acid and strong base should be 7 theoretically specking because, they produce a neutral salt on reaction. This means that the salt wont be hydrolysed or anything like that to raise the PH above 7. But during actual titration its important that we use an indicator to map the equivalence point. Generally during experiments we cannot precisely map the equivalence point and just stop at the exact instant when the equivalence point point is reached,you might have added a few extra drops of strong base which raised the Ph of resulting solution.as none can stop at exact moment.

while conducting experiment the Ph transition range of the indicator that you used might not have been near about 7 which could have led to you adding more than required NaOH .

davacd
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The equivalence point should be at pH 7, if it is higher it means that too much NaOH was added. Seems like you should indeed add more points. https://www.khanacademy.org/test-prep/mcat/chemical-processes/titrations-and-solubility-equilibria/a/acid-base-titration-curves

David Bushiri
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