A buffer contains 0.030 mol of lactic acid (pKa = 3.86) and 0.070 mol of sodium lactate per liter. 0 my HC .. wyboru OH Nat OH OH Lactic acid Sodium lactate Calculate the pH of the buffer. buffer pH: 4.23 Calculate the change in pH after adding 8.0 mL of 0.10 M HCl to 1.0 L of the buffer. buffer pH change: units Calculate the change in pH after adding 8.0 mL of 0.10 M HCl to 1.0 L of pure water. water pH change: units