Calculate the pH of a buffer system containing 1.0 M CH₃COOH and 0.85 M CH₃COONa CH₃COOH (aq) <-> H⁺ (aq) + CH3COO^- (aq) Ka = 1.8 x 10⁻⁵ What is the pH after the addition of 0.1 mole NaOH to the solution?