1. What substances are present in a buffer?
a) A weak acid and its salt with a strong conjugate base
b) A hydrolyzing salt only
c) A weak base or acid only
d) A salt only
2. Buffer capacity of a buffer solution resulting in a pH change of buffer solution by
a) one unit
b) ten units
c) seven units
d) no change in pH value of a buffer solution at all
3. The Henderson-Hasselbalch equation is ________.
a) [H+] = Ka + b) pH = pKa – log
c) pH = pKa + log d) pH = pKa + log
e) pH = log
4. Use the Henderson-Hasselbalch equation to calculate the pH of a buffer solution containing
0.250M sodium propionate and 0.350M propionic acid. The acid dissociation constant, Ka, for
propionic acid is 1.34x 10-5
.