A sample of wastewater from an industrial plant contains barium hydroxide, Ba(OH)2\text{Ba(OH)}_2Ba(OH)2, at a concentration of 0.075 mol dm-3. At 310 K (the temperature of the effluent), the ionic product of water, KwK_{\text{w}}Kw, is 2.4 × 10-14 mol2 dm-6.
What is the pH of this wastewater sample at 310 K?
12.4912.4912.49
12.8012.8012.80
12.8812.8812.88
13.1813.1813.18