[vmaggio]

What is the percent dissociation of acetic acid if the solution has pH = 4.74 and pKa = 4.74?



im sure this is a simple problem i just cant seem to figure it out, i looked all through my text book and there were no examples like this.

also i have another question how do you get the pH when you are given the %dissociation and Ka.



thanks

[Borek]

Percent dissociation definition + Henderson-Hasselbalch equation. You don't have to calculate anything, it is the simplest possible question

Hint: pH = pKa, what does it tell about log(A/HA)?

[vmaggio]

its 50% right, because at the midway point of titration pka=ph?

[Borek]

Yep.