1.  Which of the following changes the value of Kp?


     A.  A change in the total pressure.

     B.  A change in the volume.

     C.  A change in the temperature.

     D.  Addition of a reactant.


 2.  Which of the following is the correct equilibrium constant

     expression for the reaction


P4(s)  + 6 Cl2(g)   =  4 PCl3(l) ?


     A.  Kp = 1/(PCl2)6

     B.  Kc = [PCl3]4/[P4][Cl2]6

     C.  Kp = PPCl3/PP4PCl2

     D.  Kc = [Cl2]6


 3.  At some temperature Kc = 0.026 for the reaction:


A  +  B   =   2 C


     Which of the following is an equilibrium set of concentrations?


           [A], M       [B], M        [C], M


     A.     0.055        0.087         0.100

     B.     0.100        0.014         0.006

     C.     0.100        0.100         0.026

     D.     0.130        0.130         0.010


 4.  At 400 K,  Kp = 6 for the reaction


1/2 N2(g)  + 3/2 H2(g)   =   NH3(g)


     What is Kp for the reaction


2 NH3(g)   =   N2(g)  +  3 H2(g) ?


     A.  0.028

     B.  6

     C.  36

     D.  0.17


 5.  For the reaction


I2(g)  +  Cl2(g)   =   2 ICl(g)


     the relationship between Kp and Kc is


     A.  Kp = Kc

     B.  Kp = Kc(RT)

     C.  Kp = Kc(RT)-1

     D.  Kp = Kc(RT)2


 6.  For the reaction


CO(g)  +  Cl2(g)   =  COCl2(g)


     Kp = 7.5 at some temperature.  If PCO = 0.100 atm, PCl2 = 0.200 atm,

     and PCOCl2  = 0.250 atm, which of the following statements is true?


     A.  The reaction is at equilibrium.

     B.  At equilibrium PCOCl2 > 0.250 atm.

     C.  At equilibrium PCOCl2 < 0.250 atm.

     D.  At equilibrium PCO = PCl2


 7.  The following reactions occur at 500 K.  Arrange them in order of

increasing tendency to proceed to completion.




     1.  2 NOCl(g)   =  2 NO(g)  +  Cl2(g)        Kp = 1.7 x 10-2

     2.  N2O4(g)   =  2 NO2(g)                    Kp = 1.5 x 103

     3.  2 SO3(g)   =  2 SO2(g)  +  O2(g)	  Kp = 1.3 x 10-5

     4.  2 NO2(g)   =  2 NO(g)  +  O2(g)	  Kp = 5.9 x 10-5


     (1 < 2 means 2 goes farther to completion than 1).


     A.   2  <  1  <  4  <  3

     B.   3  <  4  <  1  <  2

     C.   1  <  3  <  4  <  2

     D.   4  <  3  <  1  <  2


 8.  The volume of the reaction vessel containing an equilibrium mixture

     is increased, while holding the temperature constant for the

     following reaction:


SO2Cl2(g)   =  SO2(g)  +  Cl2(g)


     When equilibrium is reestablished, which of the following statements

     is true?


     A.  The amount of Cl2 will have increased.

     B.  The amount of SO2Cl2 will have increased.

     C.  The amounts of all three species will be unchanged.

     D.  The amount of SO2 will have decreased.


 9.  The reaction


2 SO2(g)  +  O2(g)   =  2 SO3(g)


     is exothermic (delta H < 0).  If the temperature of an equilibrium

     reaction mixture is raised at constant pressure,


     A.  more SO3(g) will be formed.

     B.  more SO2(g) will react.

     C.  Kp will decrease.

     D.  the reaction will remain at equilibrium.


10.  Consider the reaction


2 NOCl(g)   =  2 NO(g)  +  Cl2(g)


     Initially, 1.25 mol of NOCl was placed in a 2.50 L reaction chamber

     at 427oC.  At equilibrium, 1.10 mol of NOCl remained.  What are

     the equilibrium concentrations of NO and Cl2 and what is the

     value of Kc?


            NO(M)      Cl2(M)         Kc

     A.     1.10       0.550       4.26 x 10-1

     B.     0.500      0.250       6.25 x 10-2

     C.     0.150      0.0750      1.39 x 10-3

     D.     0.0600     0.0300      5.58 x 10-4


11.  At 25oC, K = 0.090 for the reaction


H2O(g)  +  Cl2O(g)   =  2 HOCl(g)


     Calculate the concentration of all species at equilibrium if 1.0 mol

     of pure HOCl is placed in a sealed 2.0 L flask.


            [H2O](M)     [Cl2O](M)   [HOCl](M)

     A.      0.13	  0.13	     0.24

     B.      0.070	  0.070	     0.36

     C.      0.18	  0.18	     0.14

     D.      0.22	  0.22	     0.065


12.  The [Mg2+] is 1.45 x 10-4 M for a saturated solution of Mg(OH)2.

     Calculate the Ksp for Mg(OH)2.


     A.  2.10 x 10-8

     B.  8.41 x 10-8

     C.  1.22 x 10-11

     D.  1.19 x 10-14


13.  What is the molar solubility of AgCl (Ksp = 1.8 x 10-10) in 0.010 M

     CaCl2?


     A.  1.8 x 10-10

     B.  1.8 x 10-12

     C.  1.8 x 10-8

     D.  0.90 x 10-8


14.  What is the conjugate acid of HPO42- ?


     A.  H3PO4

     B.  H2PO4-

     C.  HPO32-

     D.  PO43-


15.  Consider a 0.100 M solution of a weak acid HA with Ka = 1.0 x 10-10.

     Which of the following statements is false?


     A.  [H+] < 0.100 M

     B.  [H+] > 1.0 x 10-7

     C.  [H+] = [A-]  +  [OH-]

     D.  [OH-] < 1.0 x 10-14


16.  The pH of a Ba(OH)2 solution is 10.10.  Calculate the [H+].


     A.  10.10 M

     B.  1.3 x 10-4 M

     C.  1.6 x 10-10 M

     D.  7.9 x 10-11 M


17.  What is the pH of 0.0050 M Ca(OH)2?


     A.  2.30

     B.  2.00

     C.  11.70

     D.  12.00


18.  Which of the following is the strongest acid?


     A.  HCOOH      Ka = 1.8 x 10-4

     B.  HClO2      Ka = 1.0 x 10-2

     C.  HCN        Ka = 7.2 x 10-10

     D.  HNO2       Ka = 4.6 x 10-4


19.  Calculate the [H+] in a 0.11 M solution of formic acid, HCOOH.

     Formic acid is a monoprotic acid with Ka = 1.7 x 10-4.


     A.  0.11 M

     B.  1.3 x 10-2 M

     C.  4.3 x 10-3 M

     D.  1.7 x 10-4 M


20.  What is the percent dissociation in a 0.200 M solution of NH3?  Kb

     for NH3 = 1.8 x 10-5.


     A.  0.95%

     B.  2.3%

     C.  4.7%

     D.  9.5%


21.  If [H+] = 0.080 M for a 0.280 M solution of an acid HA, what is Ka

     for that acid?


     A.  0.032

     B.  0.029

     C.  0.023

     D.  0.040


22.  Which of the following solutions will not be basic?


     A.  A solution of the chloride of the conjugate acid of a weak base,

         e.g., NH4Cl.

     B.  A solution of the sodium salt of the conjugate base of a weak

         acid, e.g., CH3COONa.

     C.  A solution of NaOH.

     D.  A solution of NH3.


23.  Acetic acid, CH3COOH, has a Ka of 1.8 x 10-5.  Calculate the pH

     of a 0.10 M solution of sodium acetate, CH3COONa.


     A.  4.74

     B.  5.13

     C.  8.87

     D.  11.13


24.  Calculate the pH of a solution that is 0.20 M CH3COOH and

     0.050 M HI.  Ka for CH3COOH equals 1.8 x 10-5.


     A.  0.602

     B.  1.30

     C.  0.699

     D.  2.72


25.  In which of the following pairs is the stronger acid listed first?


1.  HOCl, HClO2 

2.  H2S, H2Se   

3.  H2O, CH4    

4.  HOBr, HOI   


     A.  1 and 2

     B.  3 and 4

     C.  2 and 3

     D.  1 and 4