What is the pH of a buffer solution containing 0.2 M acetic acid and 0.1 M sodium acetate?

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Q: What is the pH of a buffer solution containing 0.2 M acetic acid and 0.1 M sodium acetate?

Solution: Using the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]) = 4.76 + log(0.1/0.2) = 5.74

Steps: 10

Step 1: Identify the components of the buffer solution. We have acetic acid (HA) and sodium acetate (A-).
Step 2: Determine the concentrations of the components. We have 0.2 M acetic acid and 0.1 M sodium acetate.
Step 3: Find the pKa of acetic acid. The pKa is approximately 4.76.
Step 4: Use the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]).
Step 5: Substitute the values into the equation: pH = 4.76 + log(0.1/0.2).
Step 6: Calculate the ratio: 0.1/0.2 = 0.5.
Step 7: Find the logarithm of 0.5: log(0.5) is approximately -0.301.
Step 8: Add this value to the pKa: pH = 4.76 - 0.301.
Step 9: Calculate the final pH: pH = 4.76 - 0.301 = 4.459.
Step 10: Round the final answer if necessary, but in this case, we keep it as 4.459.