Using the Henderson-Hasselbalch Equation, Calculate the PH of a Buffer

Multiple Choice

Using the Henderson-Hasselbalch equation, calculate the pH of a buffer solution made from 0.20 M CH₃COOH and 0.050 M CH₃COO^- that has pK_a= 4.7.

A) 5.3
B) 4.1
C) 2.5
D) 0.4
E) None of the answers is correct.