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erik [133]
3 years ago
7

If a weak acid is 25 deprotonated at ph 4 what would the pka be

Chemistry
1 answer:
elena-s [515]3 years ago
6 0

4.48

pH=pKa+log([A-/HA])

25% deprotonated tells us that A- is .25 and that the rest (75% is protonated) thats .75.

4 = pKa + log \frac{.25}{.75}

4 - log \frac{.25}{.75}  = pKa

4.48=pKa

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2 years ago
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