HO* (aq) + CHCHCOO (aq) K, 1.4 x 10 at 25C CHCHCOOH(aq) + OH(aq) K7.4 x 10-10 at 25C The acid equilibrium for CHCHCOOH and the base equilibrium for CHCHCOO are represented above. One liter of a buffer solution with pH 4.85 is made by mixing 0.100 M CHCHCOOH and 0.100 M NaCHCHCOO. if 10.0 mL of 0.500 M NaOH is added to the buffer, which of the following is most likely the resulting pH, and why? The pH will be much less than 4.85, because the buffer will respond to the addition of NaOH by producing more CHCHCOOH. CHCHCOOH(aq) + HO(1) CHCHCOO (aq) + HO(1) The pH will be much greater than 4.85, because there is a large increase in the concentration of the weak base, CHCHCOO The pH will be slightly less than 4.85, because the addition of NaOH reduces the autoionization of HO. D The pH will be slightly greater than 4.85, because some CHCHCOOH will react with the added bases, resulting in a slight decrease in (HO).