CHM 1046                      QUIZ  5                  October 4, 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 7.

                   List names in alphabetical order!

_______________________  _______________________

_______________________  _______________________

_______________________  _______________________

Points

(10)1.Using the relative strengths of acids and their conjugate
      bases shown in Figure 16.4, predict whether the following
      acid-base equilibria would lie to the right or to the left as
      written.  Over each reactant and each product, write whether
      that species is acting as an acid or as a base in the
      equilibrium reaction.

           Reaction                                        Direction of
                                                           Equilibrium


      HNO3(aq)  +  F-(aq)  þ   HF(aq)  +  NO3-(aq)         ____________



      NH4+(aq) + HCO3-(aq)  þ  NH3(aq) + H2CO3(aq)         ____________



      H2S(aq) + HSO4-   þ  HS-(aq)  +  H2SO4(aq)           ____________



      HSO4-  +  HCO3-  þ   H2CO3(aq)  +  SO4-2(aq)         ____________



      HSO4-  +  HCO3-  þ   H2SO4(aq)  +  CO3-2(aq)         ____________

(2)2. For each of the following pH values, circle the [H+] that is
      written to the correct number of significant figures.

       pH                             [H+]

      4.26      5 x 10-5  5.5 x 10-5  5.50 x 10-5  5.495 x 10-5

      3.1       8 x 10-4  7.9 x 10-4  7.94 x 10-4  7.943 x 10-4
      
      
      
(4)3. Calculate the [H+], pH, [OH-], and pOH of the following
      solutions:

      (a)  0.0016 M HCl









      (b)  0.107 M NaOH









(4)4. HClO is a weak acid with a Ka of 3.0 x 10-8.  Calculate the
      [H+] and pH of a 0.26 M solution of HClO.