Answer is: pH value of weak is 3.35. Chemical reaction (dissociation): HA(aq) → H⁺(aq) + A⁻(aq). c(HA) = 0.0055 M. α = 8.2% ÷ 100% = 0.082. [H⁺] = c(HA) · α. [H⁺] = 0.0055 M · 0.082. [H⁺] = 0.000451 M. pH = -log[H⁺]. pH = -log(0.000451 M). pH = 3.35. pH (potential of
hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.
