The pH of a solution is a measure used to evaluate the acidity of a solution. It is related to the hydronium ion concentration in the solution. It is expressed as pH = -log [H+]. Also, it is related to pOH by the equation 14 = pH + pOH. It is stated that the substance given in the problem is a strong base which means that it completely dissociates into ions. It dissociates as follows:
Ba(OH)2 = Ba^2+ + 2OH-
To determine the pH of the solution, we need to determine the OH- concentration. Then, find pOH. We do as follows:
[OH-] = 0.0064 mol Ba(OH)2 / L ( 2 mol OH- / 1 mol Ba(OH)2 ) = 0.0128 mol OH- / L
pOH = -log (0.0128) = 1.8928
pH = 14 - 1.8928 = 12.1072
