A beaker with 115 mL of an acetic acid buffer with a pH of 5.000is sitting on a bench top. The total molarity of acid and conjugatebase in this buffer is 0.100 M. A student adds 4.80 mL of a 0.420 MHCl solution to the beaker. How much will the pH change? The pKa ofacetic acid is 4.740. Express your answer numerically to twodecimal places. Use a minus ( − ) sign if the pH has decreased.
