When preparing an acetate buffer at pH 4.5 with 0.01 M solutions of acetic acid (pK_a = 4.8) and sodium acetate, the volume of acetic acid needed would be ____ the volume of sodium acetate solution.

Question

Quizplus · Accepted Answer

To prepare a buffer at pH 4.5 using acetic acid (pKa = 4.8), the Henderson-Hasselbalch equation is used: pH = pKa + log([A-]/[HA]). Solving for the ratio [A-]/[HA] gives approximately 0.32, meaning the concentration of acetic acid ([HA]) should be about twice that of sodium acetate ([A-]).

When Preparing an Acetate Buffer at PH 4