1)If 67.0 mL of 0.119 mol/L NaOH(aq) and 35.0 mL of 0.193 mol/L HA(aq) are mixed, then what is [HA] at equilibrium? Assume that HA is a weak monoprotic acid with pKa=6.23 at 25oC. 2)Determine the following characteristics of the titration curve for 25.0 mL of 0.400 M NH3(aq) titrated with 0.335 M HI(aq). (For NH3, Kb = 1.8x10-5.) (a) The initial pH : (b) The volume of HI(aq) required to reach the equivalence point : (c) The pH at the half-neutralization point. d)The pH at the equivalence point