Buffer Solutions

Step 1: Understanding the buffer equation.
The pH of a buffer solution can be calculated using the Henderson-Hasselbalch equation: where is the concentration of the base (acetate ion, ) and is the concentration of the acid (acetic acid, ).
Step 2: Substitute the given values.
- pK = 4.76
- = 0.4 M (sodium acetate)
- = 0.004 M (acetic acid)
Substitute into the equation: Step 3: Conclusion.
The pH of the buffer solution is 5.04.