CHM 1046                      QUIZ  7                 October 23, 1996


     This quiz is take-home and open book, and it is intended that
all members of the group contribute to completing it.  Only one
copy is to be submitted by the group, and all members who
participated should sign their names below.  Test is due by start
of class on Monday, October 28.

                   List names in alphabetical order!

_______________________  _______________________

_______________________  _______________________

_______________________  _______________________

Points

(6)1. Calculate the pH of a solution containing the following
      mixtures of acids and their conjugate bases.

      (a)  0.025 M formic acid and 0. 033 M sodium formate






      (b)  0.065 M hydrochloric acid and 0.025 M sodium chloride.







      (c)  0.043 M ammonia and 0.026 M ammonium chloride.








(4)2. Determine the pH of the final solution after 14.2 mL of
      0.125 M sodium hydroxide is added to 50.0 mL of 0.0975 M
      nitric acid.












(4)3. Determine the pH of the final solution after 14.2 mL of
      0.125 M sodium hydroxide is added to 50.0 mL of 0.0975 M
      acetic acid.



















(6)5. You are given 125 mL of a buffer which is 0.127 M in ammonia
      and 0.088 M in ammonium chloride.  To this buffer is added
      25.0 mL of 0.123 M perchloric acid.  Calculate the pH of the
      buffer before and after the addition of the perchloric acid.