Question

Calculate the pH of a mixture that contains 0.19 M of HNO3 and 0.27 M of HBrO.

Answer 1

Suppose we are mixing equal volumes of two solutions, one containing 0.19 moles / liter (M) and the other containing 0.27 moles / liter of hydrogen ions. If you think about it, the weaker acid will dilute the stronger acid, and the net result will be a molar solution which is the sum of the two concentrations divided by two. So 0.19 + 0.27 divided by 2 = 0.23 molar solution. This should seem reasonable because the HNO3 will be made stronger and the HBrO will be made weaker.

Therefore, [H+] = 0.23M

We know pH = -log[H+] = - log (0.23) = 0.64