Section I: Multiple Choice:
1. All of the following may change during a chemical reaction except
a. the total number of atoms in the system
b. the temperature of the system
c. the density of the system
d. the total number of molecules in the system
e. the total volume of the system
2. All of the following reactions are called combination reactions except
a.
b.
c.
d.
e.
3. A 20.0 g sample of HF is dissolved in water to give 2.0 x 102 mL of solution. The concentration of the solution is:
a. 1.0 M
b. 3.0 M
c. 0.10 M
d. 5.0 M
e. 10.0 M
4. Which of the following aqueous solutions contains the greatest number of ions?
a. 400.0 mL of a 0.10 M NaCl
b. 300.0 mL of a 0.10 M CaCl2
c. 200.0 mL of a 0.10 M FeCl3
d. 200.0 mL of a 0.10 M KBr
e. 800.0 mL of a 0.10 M sucrose
5. All of the following are weak acids except:
a. HCNO
b. HBr
c. HF
d. HNO2
e. HCN
6. The interaction between solute particles and water molecules, which tends to cause a salt to fall apart in water, is called
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a. hydration
b. polarization
c. dispersion
d. coagulation
e. conductivity
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7. Consider two organic molecules, ethanol and benzene. One dissolves in water and the other does not. Why?
a. They have different molar masses
b. One is ionic, the other is not.
c. One is an electrolyte, the other is not
d. Ethanol contains a polar O-H bond, and benzene does not
e. Two of these
8. Which of the following is a weak electrolyte in aqueous solution?
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a. HCl
b. NaCl
c. Al(NO3)3
d. HC2H3O2
e. NH4Cl
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9. Aqueous solutions of sodium sulfide and copper (II) chloride are mixed together. Which statement is correct?
a. Both NaCl and CuS precipitate from solution.
b. No precipitate forms
c. CuS will precipitate from solution
d. NaCl will precipitate from solution
e. No reaction will occur
10. Which of the following best represents the equation for the reaction of aqueous ammonia with sulfuric acid?
a.
b.
c. (aq)
d.
e.
11. The balanced net ionic equation for the reaction of solid calcium carbonate with nitric acid is
a.
b.
c.
d.
e.
12. What is the oxidation number of P in H3PO3?
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a. -3
b. 0
c. +1
d. +3
e. +7
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13. You have equal masses of different solutions dissolved to equal volumes of solution. Which of the solutes would make the solution having the highest molar concentration?
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a. NaOH
b. KCl
c. KOH
d. LiOH
e. All the same
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14. Which of the following are oxidation-reduction reactions?
I. PCl3 + Cl2 → PCl5
II. Cu + 2 Ag(NO3) → Cu(NO3)2 + 2 Ag
III. CO2 + 2 LiOH → Li2CO3 + H2O
IV. FeCl2 + 2 NaOH → Fe(OH)2 + 2 NaCl
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a. III
b. IV
c. I and II
d. I, II, and III
e. I, II, III, and IV
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15. The following reaction occurs in aqueous acid solution:
NO31- + I1- → IO31- + NO2
The oxidation state of iodine in IO31- is:
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a. 0
b. 3+
c. 3-
d. 5+
e. 5-
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16. For the reaction that occurs in a lead storage battery,
the oxidizing agent is
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a. Pb
b. PbO2
c. H+
d. HSO4-1
e. PbSO4
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17. For the oxidation of ethanol to ethanoic (acetic) acid,
(not balanced)
the number of electrons that must be added to the right side is
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a. 0
b. 1
c. 2
d. 3
e. 4
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18. When the half reaction
is balanced correctly in acid solution, the balanced half reaction will have
_______________. (use the smallest whole-number coefficients.)
a. 4H+ on the right and 2e on the left
b. 4H+ on the right and 2e on the right
c. 4H+ on the right and 1e on the right
d. 4H+ on the right and 3e on the right
e. 2H2O molecules on the left and 2e on the right
19. Which of the following statements is (are) true? Oxidation and reduction
a. cannot occur independently of each other
b. accompany all chemical changes
c. describe the loss and gain of electron(s) respectively
d. results in a change in the oxidation states of the species involved.
e. a, c and d are true
20. How much 0.54 M NaCl, “physiologic saline”, can be prepared via the dilution of 100 mL of a 6.0 M NaCl solution?
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a. 1.1 L
b. 910 mL
c. 90 mL
d. 540 mL
e. 1.9 L
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21. 350.0 mL of 2.50 M HCl are added to 400.0 mL of 5.00 M HCl. Assuming that the volumes are additive, the final concentration is
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a. 3.65 M
b. 3.83 M
c. 4.17 M
d. 4.33 M
e. 4.50 M
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22 The titration of HCl with NaOH is represented by the equation
What volume of 0.100 M HCl is required to titrate 50.0 mL of 0.500 M NaOH?
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a. 50.0 mL
b. 100. mL
c. 200. mL
d. 250. mL
e. 500. mL
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Questions 23 – 25 are related to each other
23. Aqueous solution of barium chloride and silver nitrate and mixed to form silver chloride and aqueous barium nitrate.
The molecular equation contains which of the following terms?
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a. AgCl(s)
b. 2 AgCl(s)
c. 2 Ba(NO3)3
d. BaNO3
e. 3AgCl(s)
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24. The complete ionic equation contains which of the following terms?
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a. 2 Ba 2+ (aq)
b. Cl –1
c. 2 Ag + (aq)
d. NO 3 –1 (aq)
e. 3 NO 3 – (aq)
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25. The net ionic equation contains which of the following terms?
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a. Ag + (aq)
b. Ba 2+ (aq)
c. NO 3 –1 (aq)
d. 3 NO 3 – (aq)
e. none of these
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26. In the reaction Zn + H2SO4 ---® ZnSO4 + H2, which, in any, element is oxidized?
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a. zinc
b. hydrogen
c. sulfur
d.. oxygen
e. none of these
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27. In the reaction 2 Cs (s) + Cl2 ---® 2 CsCl (s) , Cl2 is
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a. the reducing agent
b. the oxidizing agent
c. oxidized
d. the electron donor
e. two of these
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28. An unknown substance dissolves readily in water but not in benzene (a nonpolar solvent). Molecules of what type are present in the substance?
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a. neither polar nor nonpolar
b. polar
c. either polar or nonpolar
d. nonpolar
e. not enough information
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29. You have exposed electrodes of a light bulb in a solution of H2SO4 such that the light bulb is on. You add a dilute salt solution and the bulb grows dim. Which of the following could be the salt in the added solution?
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a. Ba(NO3)2
b. NaNO3
c. K2SO4
d. Mg(NO3)2
e. none of these
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30. Given the reaction
determine the number of electrons involved in this reaction.
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a. 10
b. 8
c. 6
d. 4
e. 2
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31. When is bombarded with one neutron, fission occurs, and the products are two
neutrons, and
a. b. c. d. e.
32. The radiation that has the greatest penetration power is
a. gamma b. beta c. positron d. x-ray e. alpha
33. The half-life of the radioisotope is 1.0 hr. The decay of a 160.0 g sample of the
isotope to 1.25 g requires
a. 3.0 hr b. 4.0 hr c. 5.0 hr d. 6.0 hr e. 7.0 hr
34. When 10647Ag undergoes electron capture, the nuclear product is
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a.
b.
c.
d.
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e. 10746Pb
35. When undergoes alpha emission, what is the immediate nuclear product?
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a.
b. 19482Po
c.
d.
e.
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36. For the reaction of sodium bromide with chlorine gas to form sodium chloride and bromine, the appropriate half-reactions are (ox = oxidation and re = reduction):
a. ox: Cl2 + 2 e- → 2 Cl1- re: 2 Br1- → Br2 + 2 e-
b. ox: 2 Br1- → Br2 + 2 e- re: Cl2 + 2 e- → 2 Cl1
c. ox: Cl + e- → Cl1- re: Br → Br1- + e-
d. ox: Br + 2 e- → Br2- re: 2 Cl1- → Cl2 + 2 e-
e. ox: 2 Na1+ + 2 e- → 2 Na- re: 2 Cl1- → Cl2 + 2 e-
37. Which of the following statements is not true?
a. When a metal reacts with a nonmetal, an ionic compound is formed.
b. A metal-nonmetal reaction can always be assumed to be an oxidation-reduction.
. c. Two nonmetals can undergo an oxidation-reduction reaction.
d. When two nonmetals react, the compound formed is ionic.
e. A metal-nonmetal reaction involves electron transfer
Section II : Balancing Redox Reaction
38. Balance the following oxidation reduction reaction which occurs in acidic solution:
Zn + As2O3 → AsH3 + Zn2+
39. Balance the following oxidation reduction which occurs in basic solution:
Section III: Chemical Reactions
40. A 0.307 g sample of an unknown triprotic acid is titrated to the third equivalence point using 35.2 mL of 0.106 M NaOH. Calculate the molar mass of the acid.
Hint: triprotic (tri) means how many hydrogen ions are available?
41. Describe how you would prepare 125 mL of 2.45 M solution of CuSO4 from a 12 M stock solution. Be sure to not just do the calculations, but to also explain how the whole process of making the solution would occur.
42. A solution of scandium chloride was treated with silver nitrate. The chlorine in the scandium compound was converted to silver chloride, AgCl.
A 58.9 mg sample of scandium chloride gave 167.4 mg of silver chloride. What are the mass percentages of Sc and Cl in scandium chloride? What is the empirical fomula?
43. A 3.00 g sample of an alloy (containing only Pb and Sn) was dissolved in nitric acid (HNO3). Sulfuric acid was added to this solution, which precipitated 2.93 g of PbSO4. Assuming that all of the lead was precipitated, what is the percentage of Sn in the sample? (molar mass of PbSO4 = 303.3 g/mol)
44. A 1.000 g sample of a metal chloride, MCl2, is dissolved in water and treated with excess aqueous silver nitrate. The silver chloride that formed weighed 1.286 g. Calculate the atomic mass of M.
45. Complete and balance the following molecular equations including phase labels, if a reaction occurs. Then write the net ionic equation. If no reaction occurs, write NR after the arrow.
a. Sr (OH)2 (aq) + HC2H3O2 (aq) ---®
b. NaHCO3 (s)
c. NaNO3 (aq) + CsCl (aq) ---®
d. LiCl (aq) + AgNO3 (aq) ---®
e. Li2CO3 (s) + HNO3 (aq) ---®
f. H2O2 (l)
g. NH4I (aq) + CsCl (aq) ---®
h. KClO3 (s)
i. NaI (aq) + Cl2 (aq) ---®
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