Calculate the pH of an acidic buffer solution containing 0.1 mol/dm³ of acetic acid (CH₃COOH) and 0.1 mol/dm³ of sodium acetate (CH₃COONa). The dissociation constant (Ka) for acetic acid is 1.8 x 10⁻⁵ (A-level cue bd1ba1aa focus)

The pH of the buffer solution is 4.76. This answer is anchored to Buffer action (A-level only). This version is uniquely anchored to Buffer action (A-level only). Retrieval anchor: A-level cue bd1ba1aa.

The pH of the buffer solution is 4.76. This answer is anchored to Buffer action (A-level only). is correct because it supports the objective: Calculate the pH of acidic buffer solutions.. The reasoning stays within Buffer action (A-level only) and avoids drifting into a similar A-Level Chemistry idea. This version is uniquely anchored to Buffer action (A-level only). Retrieval anchor: A-level cue bd1ba1aa. This item is treated as conceptual revision rather than a formal calculation item because the validated answer is an explanation or option choice, not a worked numerical response.