Which of the following has the strongest conjugate base? Phenol (pka 9.89) Formic acid (pKa 3.75) Boric acid (pKa 9.14) Carbonic acid (pKa 6.37) Which of the following has the lowest pH? 0.1M Phenol (pka 9.89) 0.1M Formic acid (pKa 3.75) 0.1M Boric acid (pKa 9.14) they are all the same