1. What is the strongest base that can exist in aqueous solution?

2. What is the pH of 0.020 M aqueous acetic acid? K_a = 1.8 x 10^-5.

3. Which is the STRONGEST acid of the given responses?

4. A Lewis acid-base neutralization reaction:

5. Which of the following is NOTamphoteric?

6. If 75.0 mL of 0.50 M HNO₃ and 75.0 mL of 0.50 M KOH are mixed, what is the molarity of the salt in the resulting solution?

7. What is the pH of a 0.0010 M aqueous solution of HCl?

8. What is the pH of a 0.05 M aqueous solution of Ba(OH)₂?

9. Which of the following pairs of compounds would make a good buffer solution?

10. Which of these salts would produce a basic aqueous solution?

11. The K_sp of CuI is 5.3 x 10^-12. What is the maximum possible concentration of Cu⁺ in a 0.30 M I^- solution?

12. What is the pH of a buffer which is prepared with 0.10 M formic acid, HCOOH, and 0.10 M sodium formate, Na⁺HCOO^-? The pK_a of HCOOH is 3.74.

13. If 25 mL of 0.50 M HCl is added to 50 mL of 0.25 M NaOH, what is the pH of this solution?

14. The K_sp of PbI₂ is 1.4 x 10^-8. What is the molar solubility (mol/L) for PbI₂?

15. Which of the following acids is the weakest?

16. Nitric oxide decomposes according to the equation: 2NO₂(g) --> 2NO(g) + O₂(g). If the average rate of change of NO₂ over the first 50 seconds is -4.2 x 10^-5 mol/L s, what would be the average rates of change of NO and O₂ over the same time period?

17. The following data were obtained for the reaction A + 2B --> C at 25oC. What is the rate law for the reaction?

            Exp.      Initial[A]    Initial[B]     Initial rate of Formation of C
              1       0.200 M        0.200 M         0.000422 M/S
              2       0.400 M        0.200 M         0.000845 M/s
              3       0.400 M        0.400 M         0.001689 M/s

18. Consider the following possible mechanism for the decomposition of ozone in the outer atmosphere:

For the two (2) questions following, consider the potential energy diagram for the three step reaction A + B --> C + D:

19. The activation energy for the rate determiningstep is represented by ___?

20. The overall reaction is:

21. For a given reaction, which of the following will affect the value of the rate constant, k:

22. Which of the following solutes will produce the highest solution boiling point when dissolved in water?

23. Calculate the mass of "antifreeze" (ethylene glycol, MW (molar mass) = 62 g/mol) necessary to mix with 80 L (80 Kg) of water in a radiator in order to make the water in the radiator freeze below 0oF (-17.8oC). K_f for water is -1.86oC/m.

24. When a welder uses an acetylene torch, the combustion of acetylene (C₂H₂) liberates the intense heat needed for welding metals together. The combustion reaction is: 2C₂H₂(g) + 5O₂(g) --> 4CO₂(g) + 2H₂O(g). The heat of combustion of acetylene is -1300 kJ/mol of C₂H₂. Calculate the heat liberated when 10.00 g acetylene is burned.

25. Use the following reactions (all are at 25° C) to calculate the enthalpy for the following reaction:

26. Given the following enthalpies of combustion, which fuel liberates the largest amount of energy of mole?

27. Given the following equilbrium concentrations for the reaction A(g) + 2B(g) --> 2C(g), [A]= .025 M; [B]= 0.15 M; [C]= 0.55 M; calculate the value for K_c.

For the three (3) questions following use equation CO(g) + Cl₂(g) --> COCl₂(g):

28. A mixture is prepared at 395° C in which [CO]= 1.5 M, [Cl₂]= 2.0 M and [COCl₂]= 0.10. K_c for the reaction is 1.2 x 10³ at 395° C.

29. The reaction at 395° above is exothermic. If the temperature of the reaction system is raised to 500° C

30. If the pressure on the system above is halved by doubling the volume of the container at constant temperature:

31. Which of the following describes a physical change?

32. The density of a certain liquid is 67.6 lb/ft³. What is the density of this liquid in g/mL? (1 kg = 2.20 lb; 1 in = 2.54 cm, 1 ft = 12 in)

33. How many grams of hydrogen will combine exactly with 8.00 grams of oxygen to produce water?

34. Which symbol/name pair is INCORRECT?

35. How many moles of sodium carbonate are present in 30.0 g of it?

36. Balance the reaction for the total combustion of ethanol using the set of smallest whole number coefficients. What is the balancing coefficient of the H₂O species?

37. When a solute is dissolved in an aqueous solution, some of the intermolecular forces between water molecules are disrupted. What is the most important intermolecular force between water molecules?

38. How many valence electrons does the Carbon atom possess?

39. Which of the following elements is INCORRECTLY classified?

40. A 6.13 g sample of pure KClO₃ was decomposed by heating. How many grams of O₂ gas are produced?

41. In a Nickel-Cadmium cell the following overall reaction is taking place:

42. In Problem #41, which species is the oxidizing agent?

43. Following is a schematic of a galvanic (voltaic) electrochemical cell. The standard reduction potentials for the Cd2+ and Cu2+ ions are -0.403 V and +0.337 V, respectively.

44. What is the oxidation number (valence) of the Cl atom in HClO₃?

45. Balance the following redox reaction taking place in acidic solution. H⁺ or H₂O species may need to be added.

46. Identify the INCORRECT statement concerning oxidation-reduction reactions:

47. Which of the following is the weakest acid?

48. Metalic scandium, Sc, is being deposited during the eletrolysis of a Sc³⁺ solution. If a current of 0.50 amps flows for 30.0 minutes, what mass of Sc(s) will be deposited assuming 100% of the current goes into the reduction of Sc³⁺?

KEY