Two buffer solutions are prepared using acetic acid and sodium acetate. Solution A contains 20.0 g of acetic acid (CH₃COOH) and 5.0 g of sodium acetate CH₃COONa). Solution B contains 10.0 g of acetic acid and 25.0 g of sodium acetate. What is the difference between the pH values of these two solutions? For acetic acid, K_a = 1.8 × 10^-5. A) 0.0 B) 1.0 C) 2.0 D) 2.3 E) 4.6

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The pH of a buffer solution is determined by the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]). Solution A has a lower ratio of [A-] (sodium acetate) to [HA] (acetic acid) compared to Solution B, resulting in a lower pH. Calculating the pH difference using the given masses and the equation shows a difference of approximately 1.0.

Two Buffer Solutions Are Prepared Using Acetic Acid and Sodium