A particular protocol calls for preparation of a buffered
solution at pH = 5.0 and a concentration of 0.30 M.
(a) Which of the following compounds would make the best buffer:
Formic acid (pKa = 3.75), acetic acid (pKa = 4.76), or ethylamine
(pKa = 9.0)?
(b) What concentration of acid and conjugate base would you use
to achieve the desired pH?
(c) Calculate the pH change of the buffered solution if 0.025
mol of HCl is added to 1 L of the buffer. Assume no change in
volume.