A buffer is composed of formic acid and its conjugate base, the formate ion. A. What is the pH of a solution that has a formic acid concentration of M and a sodium formate concentration of M?

a. Requires the Henderson-Hasselbalch equation.
b. Involves calculating the concentration of hydronium ions.
c. Utilizes the equilibrium constant for the acid-base reaction.
d. Considers the relationship between pH and pKa.