CHM 1046                      QUIZ  6                 October 11, 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 14.

                   List names in alphabetical order!

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Points

(5)1. Ascorbic acid (vitamin C) has two dissociable protons, with
      Ka's of 8.0 x 10e-5 and 1.6 x 10e-12 respectively.  What will be
      the pH of a 0.15 M solution of ascorbic acid?  (Can one
      neglect the second ionization?)














(5)2. Sulfurous acid (H2SO3) has two dissociable protons, with Ka's
      of 1.7 x 10e-2 and 6.4 x 10e-8 respectively.  What will be the
      pH of a 0.15 M solution of sulfurous acid?  (Can one neglect
      the second ionization?)




















(5)3. Formic acid (HCOOH, the substance causing ant bites to sting)
      is a weak acid with Ka of 1.8 x 10e-4.  Sodium formate will
      therefore hydrolyze in aqueous solution to produce some formic
      acid and hydroxide ion.  Calculate the [OH-] and pH of a
      solution of 0.035 M sodium formate.





















(5)4. A 0.25 M solution of a weak acid has a pH of 3.56.  What is
      the Ka for this acid?