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Setler [38]
3 years ago
14

Calculate the pH of a buffer solution that contains 0.25 M benzoic acid (C 6H 5CO 2H) and 0.15M sodium benzoate (C

Chemistry
1 answer:
gtnhenbr [62]3 years ago
4 0

Answer:

pH=3.97

Explanation:

Hello,

In this case, for the calculation of the pH of the given buffer we need to use the Henderson-Hasselbach equation:

pH=pKa+log(\frac{[base]}{[acid]} )

Whereas the pKa for benzoic acid is 4.19, the concentration of the base is 0.15 M (sodium benzoate) and the concentration of the acid is 0.25 M (benzoic acid), therefore, the pH turns out:

pH=4.19+log(\frac{0.15M}{0.25M} )\\\\pH=3.97

Regards.

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