posted by Wendy on .
How could you prepare a buffer if only acetic acid, HCl and NaOH are available? If you must have a weak acid and a conjugate base for a buffer, if the conjugate base is not available, how could one generate it?
This makes no sense to me. Maybe I am overlooking something?
Take acetic acid and add NaOH to it. That produces sodium acetate, the base of the acid/base system. To make this work, one needs to use acetic acid and add NaOH but not enough to completely neutralize it.
For example, if you took 10 moles acetic acid and added 5 moles NaOH, that will give you 5 mol sodium acetate (the base) and will leave 5 moles acetic acid (the acid) and that gives you the acid/base pair you want. The HCl and NaOH, added drop wise to the completed solution is for final adjustment of the pH.
Makes sense. I guess I was over thinking it. Seemed too easy to be that. thank you for your time!