A buffer contains ethanoic acid (pKa = 4.76) and sodium ethanoate with [ethanoate]/[acid] = 2. What is its pH?
Answer and explanation
Correct answer: B. 5.06
- Step 1: Henderson-Hasselbalch: . Step 2. . Answer: 5.06. Why not the others: 4.46 subtracts log 2; 4.76 would need equal concentrations; 5.36 adds 0.60 by using log 4.
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