Write the Henderson-Hasselbalch equation for a propanoic acid solution (CH3CH2CO2H, pKa = 4.874) using the symbols HA and A–, an

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Nastasia [14]

3 years ago

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Write the Henderson-Hasselbalch equation for a propanoic acid solution (CH3CH2CO2H, pKa = 4.874) using the symbols HA and A–, an

d the given pKa value for propanoic acid in the expression

Chemistry

1 answer:

Luden [163] · Answer 1 · 2022-03-19T00:48:20+03:00

The Henderson-Hasselbalch approximation is for conjugate acid-base pairs in a buffered solution. We're going to call HA a weak acid, and A- its conjugate base. The equation is as follows:
pH = pKa + log([base]/[acid]), where the brackets imply concentrations
Plugging in our symbols and the pKa value, the equation becomes:
pH = 4.874 + log([A-]/[HA])