Calculate the pH of the solution that results from each of the following mixtures. PART A 150.0 mL of 0.26 M HF with 230.0 mL of 0.32 M NaF The Ka of hydrofluoric acid is 6.8 x 10−4. Express your answer using two decimal places.
PART B 170.0 mL of 0.11 M C2H5NH2 with 270.0 mL of 0.22 M C2H5NH3Cl. Express your answer using two decimal places.

Ithink the answer is a or d.

They can measure  the amount of energy gained or lost

Answerthe half-reaction having the greatest tendency to occur at the anode:     i₂(aq) + 2e⁻  ⇄ 2i⁻  ;   e = +0.53 v======oxidation occurs at the anode. we must therefore find the half-reaction with the greatest tendency to oxidize.the given values of e are reduction potentials (the form of the half-reactions are of reduction).the lower the reduction potential, the higher the potential to oxidize. the half-cell with the lowest reduction potential will have the greatest tendency to oxidize at the anode.the half-reaction having the greatest tendency must be    i₂(aq) + 2e⁻  ⇄ 2i⁻    e = +0.53 vbecause its reduction potential is the lowest out of the three.