Abeaker with 175 ml of an acetic acid buffer with a ph of 5.00 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 5.60 ml of a 0.470 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.760. express your answer numerically to two decimal places. use a minus (- sign if the ph has decreased.