A buffer solution is prepared by mixing 0.2 moles of acetic acid and 0.1 moles of sodium acetate in 1 liter of water. If the pKa of acetic acid is 4.76, what is the pH of the solution?
- 4.76
- 4.46
- 5.06
- 7.00
📝 Detailed explanation
Henderson-Hasselbalch equation: pH = pKa + log([Salt]/[Acid]).pH = 4.76 + log(0.1 / 0.2).
pH = 4.76 + log(0.5).
pH = 4.76 - 0.30 = 4.46.