General Chemistry The Essential Concept 7Th Edition Raymond By Chang – Test Bank

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General Chemistry The Essential Concept 7Th Edition Raymond By Chang – Test Bank

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Chapter 02: Atoms Molecules and Ions

 

A periodic table is required to work many of the problems in this chapter.

 

1. In a cathode ray tube
2. A) electrons pass from the anode to the cathode.
3. B) electrons pass from the cathode to the anode.
4. C) protons pass from the anode to the cathode.
5. D) protons pass from the cathode to the anode.

Ans:  B     Category:  Medium     Section:  2.2

 

2. The elements in a column of the periodic table are known as
3. A)     B)  a period.    C)  noble gases.    D)  a group.    E)  nonmetals.

Ans:  D     Category:  Easy     Section:  2.4

 

3. Which of the following elements is most likely to be a good conductor of electricity?
4. A) N    B)  S    C)  He    D)  Cl    E)  Fe

Ans:  E     Category:  Easy     Section:  2.4

 

4. An anion is defined as
5. A) a charged atom or group of atoms with a net negative charge.
6. B) a stable atom.
7. C) a group of stable atoms.
8. D) an atom or group of atoms with a net positive charge.

Ans:  A     Category:  Easy     Section:  2.5

 

5. The scientist who determined the magnitude of the electric charge of the electron was
6. A) John Dalton.                                          D)      Henry Moseley.
7. B) Robert Millikan.                                    E)      Chang.
8. C) J. Thomson.

Ans:  B     Category:  Easy     Section:  2.2

 

6. When J. J. Thomson discovered the electron, what physical property of the electron did he measure?
7. A) its charge, e                                           D)      its mass, m
8. B) its charge-to-mass ratio, e/m                  E)      its atomic number, Z
9. C) its temperature, T

Ans:  B     Category:  Easy     Section:  2.2

 

7. Which of the following scientists developed the nuclear model of the atom?
8. A) John Dalton                                           D)      Henry Moseley
9. B) Robert Millikan                                     E)      Ernest Rutherford
10. C) J. Thomson

Ans:  E     Category:  Easy     Section:  2.2

 

8. Rutherford’s experiment with alpha particle scattering by gold foil established that
9. A) protons are not evenly distributed throughout an atom.
10. B) electrons have a negative charge.
11. C) electrons have a positive charge.
12. D) atoms are made of protons, neutrons, and electrons.
13. E) protons are 1840 times heavier than electrons.

Ans:  A     Category:  Medium     Section:  2.2

 

9. Atoms of the same element with different mass numbers are called
10. A)     B)  neutrons.    C)  allotropes.    D)  chemical families.    E)  isotopes.

Ans:  E     Category:  Easy     Section:  2.3

 

10. How many neutrons are there in an atom of uranium whose mass number is 235?
11. A) 92    B)  143    C)  235    D)  238    E)  327

Ans:  B     Category:  Easy     Section:  2.3

 

11. How many protons are there in an atom of uranium whose mass number is 235?
12. A) 92    B)  143    C)  235    D)  238    E)  327

Ans:  A     Category:  Easy     Section:  2.3

 

12. An atom of the isotope chlorine-37 consists of how many protons, neutrons, and electrons? (p = proton, n = neutron, e = electron)
13. A) 17 p, 18.45 n, 17 e                                 D)      17 p, 37 n, 17 e
14. B) 17 p, 20 n, 7 e                                        E)      20 p, 17 n, 20 e
15. C) 17 p, 20 n, 17 e

Ans:  C     Category:  Medium     Section:  2.3

 

13. Give the number of protons (p), electrons (e), and neutrons (n) in one atom of nickel-62.
14. A) 28 p, 28 e, 28 n                                      D)      62 p, 28 e, 28 n
15. B) 28 p, 28 e, 34 n                                      E)      62 p, 62 e, 28 n
16. C) 28 p, 28 e, 62 n

Ans:  B     Category:  Medium     Section:  2.3

 

14. Which one of the following is an ion?
15. A) B³⁺    B)  NaCl    C)  He    D)  ¹⁴C    E)  none of the above

Ans:  A     Category:  Easy     Section:  2.5

 

15. Which one of the following elements is most likely to form a 2+ ion?
16. A) beryllium    B)  carbon    C)  fluorine    D)  oxygen    E)  sodium

Ans:  A     Category:  Medium     Section:  2.5

 

16. Which one of the following elements is most likely to form a 2– ion?
17. A) scandium    B)  selenium    C)  silicon    D)  strontium    E)  iodine

Ans:  B     Category:  Medium     Section:  2.5

 

17. Two isotopes of an element differ in their
18. A)                                                   D)      number of protons.
19. B) atomic number.                                      E)      number of electrons.
20. C) atomic mass.

Ans:  C     Category:  Easy     Section:  2.3

 

18. A magnesium ion, Mg²⁺, has
19. A) 12 protons and 13 electrons.                 D)      24 protons and 22 electrons.
20. B) 24 protons and 26 electrons.                 E)      12 protons and 14 electrons.
21. C) 12 protons and 10 electrons.

Ans:  C     Category:  Medium     Section:  2.5

 

19. An aluminum ion, Al³⁺, has:
20. A) 13 protons and 13 electrons                  D)      13 protons and 10 electrons
21. B) 27 protons and 24 electrons                  E)      10 protons and 13 electrons
22. C) 16 protons and 13 electrons

Ans:  D     Category:  Medium     Section:  2.5

 

20. An oxide ion, O^2–, has:
21. A) 8 protons and 10 electrons                    D)      8 protons and 7 electrons
22. B) 10 protons and 8 electrons                    E)      10 protons and 7 electrons
23. C) 8 protons and 9 electrons

Ans:  A     Category:  Medium     Section:  2.5

 

21. A phosphide ion has:
22. A) 10 protons and 13 electrons                  D)      15 protons and 18 electrons
23. B) 12 protons and 15 electrons                  E)      18 protons and 21 electrons
24. C) 15 protons and 15 electrons

Ans:  D     Category:  Medium     Section:  2.5

 

22. An iron(II) ion has:
23. A) 24 electrons and a charge of 2+            D)      28 electrons and a charge of 2+
24. B) 24 electrons and a charge of 2–            E)      28 electrons and a charge of 2–
25. C) 26 electrons and a charge of 2+

Ans:  A     Category:  Medium     Section:  2.5

 

23. How many protons and electrons are present in one Br^–  ion?
24. A) 35 p,   35 e                                             D)      35 p,   36 e
25. B) 80 p,   81 e                                             E)      80 p,   34 e
26. C) 35 p,   34 e

Ans:  D     Category:  Medium     Section:  2.5

 

24. Which of the following pairs of elements would be most likely to form an ionic compound?
25. A) P and Br    B)  Cu and K    C)  C and O    D)  O and Zn    E)  Al and Rb

Ans:  D     Category:  Medium     Section:  2.6

 

25. Which pair of elements would be most likely to form an ionic compound?
26. A) P and Br    B)  Zn and K    C)  F and Al    D)  C and S    E)  Al and Rb

Ans:  C     Category:  Medium     Section:  2.6

 

26. Given that the ion ClO₃^– is named chlorate, what is the ion ClO₄^– named?
27. A) chloride    B)  chlorite    C)  hypochlorite    D)  perchlorite    E)  perchlorate

Ans:  E     Category:  Medium     Section:  2.7

 

27. What is the formula for the ionic compound formed by calcium ions and nitrate ions?
28. A) Ca₃N₂    B)  Ca(NO₃)₂    C)  Ca₂NO₃    D)  Ca₂NO₂    E)  CaNO₃

Ans:  B     Category:  Medium     Section:  2.7

 

28. What is the formula for the ionic compound formed by calcium and selenium?
29. A) CaSe    B)  Ca₂Se    C)  CaSe₂    D)  Ca₃Se    E)  CaSe₃

Ans:  A     Category:  Medium     Section:  2.6

 

29. What is the formula for the ionic compound formed by magnesium and iodine?
30. A) MgI    B)  Mg₂I    C)  MgI₂    D)  MgI₃    E)  Mg₃I

Ans:  C     Category:  Medium     Section:  2.6

 

30. What is the formula for the binary compound formed by potassium and nitrogen?
31. A) KN    B)  K₂N    C)  NK₂    D)  K₃N    E)  NK₃

Ans:  D     Category:  Medium     Section:  2.6

 

31. Predict the formula for the binary compound formed between barium and phosphorus.
32. A) BaP    B)  Ba₂P    C)  BaP₂    D)  Ba₂P₃    E)  Ba₃P₂

Ans:  E     Category:  Medium     Section:  2.6

 

32. Name the binary compound formed between barium and phosphorus.
33. A) barium phosphorus                                D)      barium diphosphate
34. B) barium phosphide                                  E)      barium triphosphide
35. C) barium phosphate

Ans:  B     Category:  Medium     Section:  2.7

 

33. Which is the correct formula for copper(II) phosphate?
34. A) Cu₂PO₄    B)  Cu₃(PO₄)₂    C)  Cu₂PO₃    D)  Cu(PO₄)₂    E)  Cu(PO₃)₂

Ans:  B     Category:  Medium     Section:  2.7

 

34. The chemical name for ClO₃^– is chlorate ion.  Therefore, the name of HClO₃ is
35. A) hydrochloric acid.                                 D)      chlorous acid.
36. B)                                             E)      chloric acid.
37. C) hydrogen trioxychloride.

Ans:  E     Category:  Medium     Section:  2.7

 

35. The chemical name for ClO₂^–  is chlorite ion.  Therefore, the name of HClO₂ is
36. A) hydrochloric acid.                                 D)      chlorous acid.
37. B)                                             E)      chloric acid.
38. C) hydrogen dioxychloride.

Ans:  D     Category:  Medium     Section:  2.7

 

36. Which of the following is the formula for hydrobromic acid?
37. A) KBr    B)  HBr    C)  HBrO    D)  HBrO₂    E)  HBrO₃

Ans:  B     Category:  Medium     Section:  2.7

 

37. The formula for calcium phosphate is
38. A) CaPO₄.    B)  Ca₃(PO₄)₂.    C)  Ca₂(PO₄)₃.    D)  Ca₃P₂.    E)  Ca₃(PO₃)₂.

Ans:  B     Category:  Medium     Section:  2.7

 

38. The formula for magnesium sulfate is
39. A)     B)  MgS.    C)  MnSO₃.    D)  MgSO₄.

Ans:  D     Category:  Medium     Section:  2.7

 

39. The formula for sodium sulfide is
40. A)     B)  K₂S.    C)  NaS₂.    D)  Na₂S.    E)  SeS.

Ans:  D     Category:  Medium     Section:  2.7

 

40. The correct name for NH₄NO₃ is
41. A) ammonium nitrate.                                D)      hydrogen nitrogen oxide.
42. B) ammonium nitrogen trioxide.                E)      hydrogen nitrate.
43. C) ammonia nitrogen oxide.

Ans:  A     Category:  Medium     Section:  2.7

 

41. The correct name for Ba(OH)₂ is
42. A) barium hydrogen oxide.                        D)      beryllium hydroxide.
43. B) boron hydroxide.                                   E)      barium hydroxide.
44. C) barium hydrate.

Ans:  E     Category:  Medium     Section:  2.7

 

42. The correct name for KHCO₃ is
43. A) calcium bicarbonate.                              D)      calcium hydrogen carbon trioxide.
44. B) calcium carbonate.                                 E)      potassium hydrogen carbonate.
45. C) potassium carbonate.

Ans:  E     Category:  Medium     Section:  2.7

 

43. The correct name for CuSO₄·5H₂O is
44. A) copper sulfate acid.                               D)      copper(II) sulfate pentahydrate.
45. B) copper sulfate pentahydrate.                 E)      copper(V) sulfate hydrate.
46. C) copper(II) sulfate acid.

Ans:  D     Category:  Medium     Section:  2.7

 

44. Give the formula for cobalt(II) chlorate dihydrate:
45. A) CoCl₂2H₂O                                          D)      Co(ClO₃)₂·2H₂O
46. B) CoClO₃(H₂O)₂                                       E)      Co₂(ClO₃)₃2H₂O
47. C) Co(ClO₃)₂(H₂O)₂

Ans:  D     Category:  Medium     Section:  2.7

 

45. The Stock system name for Mn₂O₇ is
46. A) dimanganese heptaoxide.                      D)      manganese(II) oxide.
47. B) magnesium oxide.                                 E)      manganese(III) oxide.
48. C) manganese(VII) oxide.

Ans:  C     Category:  Medium     Section:  2.7

 

46. The Stock system name for As₂S₅ is
47. A) arsenic(V) sulfide.                                 D)      arsenic(V) sulfate.
48. B) diarsenic pentasulfide.                          E)      diarsenic sulfate.
49. C) arsenic(III) sulfide.

Ans:  A     Category:  Medium     Section:  2.7

 

47. Consistent with vanadium being a transition metal, the name for VSO₄ should be
48. A) vanadium sulfide.                                  D)      vanadium (II) sulfate.
49. B) vanadium (I) sulfite.                              E)      vanadium sulfur tetraoxide.
50. C) vanadium (I) sulfate.

Ans:  D     Category:  Medium     Section:  2.7

 

48. Which is the correct formula for lead(IV) chloride?
49. A) Pb₄Cl    B)  PbCl₂    C)  PbCl₃    D)  PbCl₄    E)  Pb₂Cl₄

Ans:  D     Category:  Medium     Section:  2.7

 

49. The chemical formula for iron(II) nitrate is:
50. A) Fe₂(NO₃)₃    B)  Ir(NO₂)₂    C)  Fe₂N₃    D)  Fe(NO₃)₂    E)  Fe(NO₂)₂

Ans:  D     Category:  Medium     Section:  2.7

 

50. The Stock system name for Co₂(SO₃)₃ is:
51. A) cobalt sulfate                                         D)      cobalt(III) sulfite
52. B) cobalt(II) sulfite                                    E)      cobalt(III) sulfate
53. C) cobalt(II) sulfate

Ans:  D     Category:  Medium     Section:  2.7

 

51. The Stock system name for CrO₃ is:
52. A) chromium oxide                                    D)      chromium(III) oxide
53. B) chromium(II) oxide                               E)      chromium(VI) oxide
54. C) chromium(III) trioxide

Ans:  E     Category:  Medium     Section:  2.7

 

52. The straight chain hydrocarbon that contains six carbon atoms is
53. A)     B)  butane.    C)  pentane.    D)  hexane.    E)  heptane.

Ans:  D     Category:  Medium     Section:  2.8

 

53. The mineral pyrolusite is a compound of manganese-55 and oxygen-16.  If 63% of the      mass of pyrolusite is due to manganese, what is the empirical formula of pyrolusite?
54. A) MnO    B)  Mn₂O    C)  Mn₂O₂    D)  MnO₂    E)  none of these

Ans:  D     Category:  Difficult

 

54. The mineral manganosite is a compound of manganese-55 and oxygen-16.  If 77% of the   mass of manganosite is due to manganese, what is the empirical formula of manganosite?
55. A) MnO    B)  Mn₂O    C)  Mn₂O₂    D)  MnO₂    E)  none of these

Ans:  A     Category:  Difficult     Section:  2.6

 

55. The mineral hausmannite is a compound of manganese-55 and oxygen-16.  If 72% of the  mass of hausmannite is due to manganese, what is the empirical formula of hausmannite?
56. A) MnO    B)  Mn₃O    C)  Mn₃O₄    D)  Mn₄O₃    E)  MnO₃

Ans:  C     Category:  Difficult     Section:  2.6

 

56. Zircon is a mineral with the empirical formula ZrSiO₄.  If all the zirconium is ⁹⁰Zr, all the silicon is ²⁸Si, and all the oxygen is ¹⁶O, what mass of oxygen is present in 10. g of zircon?
57. A) 88 g    B)  1.2 g    C)  1.8 g    D)  3.5 g    E)  5.4 g

Ans:  D     Category:  Medium     Section:  2.3

 

57. The mineral orpiment, having the empirical formula As₂S₃, was used in ancient times as a cosmetic.  What mass of arsenic is present in 5.0 g of orpiment? [Given: naturally occurring arsenic is all arsenic-75; assume that all naturally occurring sulfur is sulfur-32 (only approximately true)]
58. A) 61 g    B)  3.0 g    C)  1.5 g    D)  2.0 g    E)  3.5 g

Ans:  B     Category:  Medium     Section:  2.3

 

58. Which of the following elements is chemically similar to magnesium?
59. A) sulfur    B)  calcium    C)  iron    D)  nickel    E)  potassium

Ans:  B     Category:  Medium     Section:  2.4

 

59. Which of the following elements is chemically similar to oxygen?
60. A) sulfur    B)  calcium    C)  iron    D)  nickel    E)  sodium

Ans:  A     Category:  Medium     Section:  2.4

 

60. Which of the following elements is chemically similar to potassium?
61. A) calcium    B)  arsenic    C)  phosphorus    D)  cerium    E)  cesium

Ans:  E     Category:  Medium     Section:  2.4

 

61. Describe the contributions of Marie Curie.

Ans:  (note that answers will vary)  Marie Curie discovered two new elements, and is one of three people to win two Nobel Prizes.  She also suggested the term “radioactivity” to describe the spontaneous emission of particles and/or radiation.

Category:  Easy     Section:  2.1

 

62. What is the law of conservation of mass?

Ans:  Matter can be neither created nor destroyed.

Category:  Easy     Section:  2.1

 

63. What are the three subatomic particles that are important in chemistry?

Ans:  electrons, protons, and neutrons

Category:  Easy     Section:  2.2

 

64. What are the three types of radiation produced by the decay of substances like uranium?

Ans:  Alpha, beta, and gamma radiation

Category:  Easy     Section:  2.1

 

65. How many electrons, protons, and neutrons does an iron-55 atom have?

Ans:  26 electrons, 26 protons, and 29 neutrons

Category:  Medium     Section:  2.3

 

66. Define the term molecule.

Ans:  A molecule is an aggregate of at least two atoms in a definite arrangement held together by chemical forces.

Category:  Easy     Section:  2.5

 

67. What are the seven elements that naturally occur as diatomic molecules?

Ans:  Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine

Category:  Medium     Section:  2.5

 

68. Define ion.

Ans:  An ion is an atom or group of atoms that has a net positive or negative charge.

Category:  Easy     Section:  2.5

 

69. In the early 1900s, Ernest Rutherford performed an experiment with gold foil targets and alpha particles to probe the structure of the atoms. He observed that most of these alpha particles penetrated the foil undeflected. Realizing that atoms are electrically neutral (that is, they have equal numbers of protons and electrons) and that the mass of a proton is significantly greater than the mass of an electron, use Rutherford’s data to propose a structural model of an atom.

Ans:  (Answers will vary.) Atoms are mostly empty space. The mass is concentrated mostly at the center of the atom.

Category:  Medium     Section:  2.2

 

Use the following to answer questions 70-76:

 

 

70. Use the periodic table above to show where the alkali metals are located.

Ans:  Group 1A

Category:  Easy     Section:  2.4

 

71. Use the periodic table above to show where the alkaline earth metals are located.

Ans:  Group 2A

Category:  Easy     Section:  2.4

 

72. Use the periodic table above to show where the metals are located.

Ans:  Group 2A

Category:  Easy     Section:  2.4

 

73. Use the periodic table above to show where the metalloids are located.

Ans:  Group 2A

Category:  Medium     Section:  2.4

 

74. Use the periodic table above to show where the nonmetals are located.

Ans:  Group 2A

Category:  Easy     Section:  2.4

 

75. Use the periodic table above to show where the halogen elements are located.

Ans:  Group 7A

Category:  Easy     Section:  2.4

 

76. Use the periodic table above to show where the noble gases are located.

Ans:  Group 8A

Category:  Easy     Section:  2.4

 

77. How many protons are there in one atom of nickel?

Ans:  28

Category:  Medium     Section:  2.3

 

78. How many protons are there in one atom of magnesium?

Ans:  12

Category:  Medium     Section:  2.3

 

79. How many protons are there in one atom of xenon?

Ans:  54

Category:  Medium     Section:  2.3

 

80. How many protons are there in one atom of uranium?

Ans:  92

Category:  Medium     Section:  2.3

 

81. A molecule of antifreeze, ethylene glycol, has the formula C₂H₄(OH)₂.  How many atoms are there in one molecule of antifreeze?

Ans:  10

Category:  Easy     Section:  2.5

 

82. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom of ³H?

Ans:  4

Category:  Medium     Section:  2.3

 

83. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom of ⁴⁰Ca?

Ans:  60

Category:  Medium     Section:  2.3

 

84. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom  of ¹⁸F?

Ans:  27

Category:  Medium     Section:  2.3

 

85. How many atoms are in one molecule of CaCl₂?

Ans:  3

Category:  Easy     Section:  2.5

 

86. How many atoms are in one molecule of C₆H₁₂O₆?

Ans:  24

Category:  Easy     Section:  2.5

 

87. Give the formula for potassium oxide.

Ans:  K₂O

Category:  Medium     Section:  2.7

 

88. Give the formula for calcium chloride.

Ans:  CaCl₂

Category:  Medium     Section:  2.7

 

89. Give the formula for carbon disulfide.

Ans:  CS₂

Category:  Medium     Section:  2.7

 

90. Give the formula for lithium hydroxide.

Ans:  LiOH

Category:  Medium     Section:  2.7

 

91. Give the formula for nickel(II) sulfate.

Ans:  NiSO₄

Category:  Medium     Section:  2.7

 

92. Name the following binary compound: FeS.

Ans:  iron(II) sulfide

Category:  Medium     Section:  2.7

 

93. Name the following binary compound: NaH.

Ans:  sodium hydride

Category:  Medium     Section:  2.7

 

94. Name the following binary compound: MnCl₂.

Ans:  manganese(II) chloride

Category:  Medium     Section:  2.7

 

95. Name the following binary compound: AgCl.

Ans:  silver chloride; may accept silver(I) chloride.

Category:  Medium     Section:  2.7

 

96. Name the following binary compound: Fe₂O₃.

Ans:  iron(III) oxide (or ferric oxide)

Category:  Medium     Section:  2.7

 

97. Name the following ternary compound: CuCO₃.

Ans:  copper(II) carbonate

Category:  Medium     Section:  2.7

 

98. Name the following ternary compound: FeSO₄.

Ans:  iron(II) sulfate

Category:  Medium     Section:  2.7

 

99. Name the following ternary compound: Na₃PO₄.

Ans:  sodium phosphate

Category:  Medium     Section:  2.7

 

100. Name the following ternary compound: Al(NO₃)₃.

Ans:  aluminum nitrate

Category:  Medium     Section:  2.7

 

101. Name the following compound:  Cl₂O₇.

Ans:  dichlorine heptaoxide, or dichlorine heptoxide

Category:  Medium     Section:  2.7

 

102. Name the straight chain hydrocarbon that contains eight carbon atoms.

Ans:  octane

Category:  Medium     Section:  2.8

 

103. The table below describes four atoms.

 

	Atom A	Atom B	Atom C	Atom D
Number of protons	79	80	80	79
Number of neutrons	118	120	118	120
Number of electrons	79	80	80	79

 

Which atoms represent the same element?

Ans:  Atoms A and D represent the same element, and atoms B and C represent the same element.

Category:  Medium     Section:  2.3

 

104. Consider a neutral atom of the following isotope of sulfur:

 

How many electrons, protons, and neutrons does the atom contain?

Ans:  16 electrons, 16 protons, and 18 neutrons

Category:  Medium     Section:  2.3

 

105. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of calcium?

 

Ans:  20 electrons, 20 protons, and 24 neutrons

Category:  Medium     Section:  2.3

 

106. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of krypton?

 

Ans:  36 electrons, 36 protons, and 48 neutrons

Category:  Medium     Section:  2.3

 

107. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium?

 

Ans:  64 electrons, 64 protons, and 96 neutrons

Category:  Medium     Section:  2.3

 

108. Write the names and symbols of two metals and two nonmetals. Identify which are the metals and which are the nonmetals.

Ans:  (Answers will vary.) Metals: iron, Fe; sodium, Na; etc. Nonmetals: chlorine, Cl; nitrogen, N; etc.

Category:  Easy     Section:  2.4

 

109. Predict the formula for the binary compound formed between potassium and sulfur.

Ans:  K₂S

Category:  Medium     Section:  2.6

 

110. Predict the formula for the binary compound formed between aluminum and fluorine.

Ans:  AlF₃

Category:  Medium     Section:  2.6

 

111. Give the formula of magnesium nitrate.

Ans:  Mg(NO₃)₂

Category:  Medium     Section:  2.7

 

112. Give the formula of calcium phosphate.

Ans:  Ca₃(PO₄)₂

Category:  Medium     Section:  2.7

 

113. Give the formula of iron(II) phosphate.

Ans:  Fe₃(PO₄)₂

Category:  Medium     Section:  2.7

 

114. Give the formula of copper(II) bromide.

Ans:  CuBr₂

Category:  Medium     Section:  2.7

 

115. Give the formula of ammonium sulfate.

Ans:  (NH₄)₂SO₄

Category:  Medium     Section:  2.7

 

116. Give the formula of hydrochloric acid.

Ans:  HCl

Category:  Medium     Section:  2.7

 

117. Give the formula of carbonic acid.

Ans:  H₂CO₃

Category:  Medium     Section:  2.7

 

118. Give the formula of nitric acid.

Ans:  HNO₃

Category:  Medium     Section:  2.7

 

119. Give the formula of sulfuric acid.

Ans:  H₂SO₄

Category:  Medium     Section:  2.7

 

120. Write the formula for the acid formed from the fluoride anion, and then name the acid.

Ans:  HF, hydrofluoric acid

Category:  Medium     Section:  2.7

 

121. Write the formula for the acid formed from the nitrite anion, and then name the acid.

Ans:  HNO₂, nitrous acid

Category:  Medium     Section:  2.7

 

122. Write the formula for the acid formed from the permanganate anion, and then name the acid.

Ans:  HMnO₄, permanganic acid

Category:  Medium     Section:  2.7

 

123. Write the formula for the acid formed from the hydrogen sulfate anion, and then name the acid.

Ans:  H₂SO₄, sulfuric acid

Category:  Difficult     Section:  2.7

 

124. The elements known as the halogens are useful as disinfectants. Name two halogens.

Ans:  (two of these) fluorine, chlorine, bromine, iodine

Category:  Medium     Section:  2.4

 

125. Define allotrope.

Ans:  An allotrope is one of the two or more distinct forms of an element.

Category:  Easy     Section:  2.6

 

126. What are isotopes?

Ans:  Atoms of the same element that have the same atomic number but different mass numbers.

Category:  Easy     Section:  2.3

 

127. Name the following compound: NaNO₂.

Ans:  sodium nitrite

Category:  Medium     Section:  2.7

 

128. Name the following compound: KCl.

Ans:  potassium chloride

Category:  Medium     Section:  2.7

 

129. Name the following compound: Mg(NO₃)₂.

Ans:  magnesium nitrate

Category:  Medium     Section:  2.7

 

130. Write the formula of ammonium chlorate.

Ans:  NH₄ClO₃

Category:  Medium     Section:  2.7

 

131. Write the formula of lead(II) chloride.

Ans:  PbCl₂

Category:  Medium     Section:  2.7

 

132. Write the formula of calcium carbonate.

Ans:  CaCO₃

Category:  Medium     Section:  2.7

 

133. The formula for isopropyl alcohol is sometimes written as (CH₃)₂CHOH to better indicate how the atoms are connected. How many hydrogen atoms would be contained in 3 dozen isopropyl alcohol molecules?

Ans:  288

Category:  Medium     Section:  2.5

 

134. Almost all the mass of an atom is concentrated in the nucleus.

Ans:  True     Category:  Easy

 

135. Marie Curie suggested the name “radioactivity” to describe the spontaneous emission of particles and/or radiation.

Ans:  True     Category:  Easy

 

136. Using a cathode ray tube, J. J. Thomson determined the magnitude of the electric charge on the electron.

Ans:  False     Category:  Easy

 

137. When a beam of alpha particles passes between two electrically charged plates, the beam is deflected toward the positive plate.

Ans:  False     Category:  Medium

 

138. The proton is about 1840 times heavier than the electron.

Ans:  True     Category:  Easy

 

139. The atomic number is equal to the number of protons in the nucleus of each atom of an element.

Ans:  True     Category:  Easy

 

140. The number of neutrons in all atoms of an element is the same.

Ans:  False     Category:  Medium

Chapter 04: Reactions in Aqueous Solution

 

1. Which of the following compounds is a strong electrolyte?
2. A) H₂O    B)  CH₃OH    C)  CH₃CH₂OH    D)  HF    E)  NaF

Ans:  E     Category:  Easy     Section:  4.1

 

2. Which of the following compounds is a weak electrolyte?
3. A) HNO₃    B)  NaNO₃    C)  HNO₂    D)  NaNO₂    E)  NaOH

Ans:  C     Category:  Easy     Section:  4.1

 

3. Which of the following compounds is a strong electrolyte?
4. A) H₂O                                                       D)      CH₃CH₂OH (ethanol)
5. B) N₂                                                          E)      KOH
6. C) CH₃COOH (acetic acid)

Ans:  E     Category:  Easy     Section:  4.1

 

4. Which of the following compounds is a weak electrolyte?
5. A) HCl                                                        D)      O₂
6. B) CH₃COOH (acetic acid)                       E)      NaCl
7. C) C₆H₁₂O₆ (glucose)

Ans:  B     Category:  Easy     Section:  4.1

 

5. Which of the following compounds is a weak electrolyte?
6. A) HCl    B)  NH₃    C)  C₆H₁₂O₆ (glucose)    D)  N₂    E)  KCl

Ans:  B     Category:  Easy     Section:  4.1

 

6. Which of the following compounds is a nonelectrolyte?
7. A) NaF                                                       D)      NaOH
8. B) HNO₃                                                    E)      C₆H₁₂O₆ (glucose)
9. C) CH₃COOH (acetic acid)

Ans:  E     Category:  Easy     Section:  4.1

 

7. Which of the following compounds is a nonelectrolyte?
8. A) NaOH                                                    D)      KF
9. B) HNO₃                                                    E)      CH₃COOH (acetic acid)
10. C) C₂H₆O (ethanol)

Ans:  C     Category:  Easy     Section:  4.1

 

8. Identify the major ionic species present in an aqueous solution of Na₂CO₃.
9. A) Na₂⁺, CO₃^2–                                           D)      Na⁺, C⁺, O^2–
10. B) Na₂⁺, C^{2 –}, O₃                                         E)      Na⁺, CO₃^2–
11. C) Na⁺, C⁴⁺, O₃^2–

Ans:  E     Category:  Easy     Section:  4.1

 

9. Identify the major ionic species present in an aqueous solution of K₂SO₄.
10. A) K²⁺, S⁶⁺, O₄^8–                                         D)      2K⁺, S⁶⁺, 4O^2–
11. B) K²⁺, S⁶⁺, 4O^2–                                        E)      2K⁺, SO₄^2–
12. C) 2K⁺, S⁶⁺, O₄^8–

Ans:  E     Category:  Easy     Section:  4.1

 

10. The distinguishing characteristic of all electrolyte solutions is that they
11. A) contain molecules.                                 D)      always contain acids.
12. B) conduct electricity.                                E)      conduct heat.
13. C) react with other solutions.

Ans:  B     Category:  Easy     Section:  4.1

 

11. Based on the solubility rules, which one of the following compounds should be insoluble in water?
12. A) NaCl    B)  MgBr₂    C)  FeCl₂    D)  AgBr    E)  ZnCl₂

Ans:  D     Category:  Easy     Section:  4.2

 

12. Based on the solubility rules, which one of the following compounds should be insoluble in water?
13. A) Na₂SO₄    B)  BaSO₄    C)  CuSO₄    D)  MgSO₄    E)  Rb₂SO₄

Ans:  B     Category:  Easy     Section:  4.2

 

13. Based on the solubility rules, which one of the following compounds should be insoluble in water?
14. A) CaCO₃    B)  (NH₄)₂CO₃    C)  Na₂CO₃    D)  K₂CO₃    E)  KNO₃

Ans:  A     Category:  Easy     Section:  4.2

 

14. Based on the solubility rules, which one of the following should be soluble in water?
15. A) Hg₂Cl₂    B)  Na₂S    C)  Ag₂CO₃    D)  Ag₂S    E)  BaSO₄

Ans:  B     Category:  Easy     Section:  4.2

 

15. Based on the solubility rules, which one of the following should be soluble in water?
16. A) AgBr    B)  AgCl    C)  Ag₂CO₃    D)  AgNO₃    E)  Ag₂S

Ans:  D     Category:  Easy     Section:  4.2

 

16. Based on the solubility rules, which one of the following should be soluble in water?
17. A) (NH₄)₃PO₄    B)  Ca₃(PO₄)₂    C)  AlPO₄    D)  Ag₃PO₄    E)  Mg₃(PO₄)₂

Ans:  A     Category:  Easy     Section:  4.2

 

17. Based on the solubility rules, which one of the following should be soluble in water?
18. A) CaSO₄    B)  BaSO₄    C)  PbSO₄    D)  K₂SO₄    E)  AgCl

Ans:  D     Category:  Easy     Section:  4.2

 

18. Based on the solubility rules, which of the following will occur when a solution containing about 0.1 g of Pb(NO₃)₂(aq) is mixed with a solution containing 0.1 g of KI(aq) /100 mL?
19. A) KNO₃ will precipitate; Pb²⁺ and I^– are spectator ions.
20. B) No precipitate will form.
21. C) Pb(NO₃)₂ will precipitate; K⁺ and I^– are spectator ions.
22. D) PbI₂ will precipitate; K⁺ and NO₃^–  are spectator ions.
23. E) Pb²⁺ and I^– are spectator ions, and PbI₂ will precipitate.

Ans:  D     Category:  Medium     Section:  4.2

 

19. Based on the solubility rules, which of the following will occur if solutions of CuSO₄(aq) and BaCl₂(aq) are mixed?
20. A) CuCl₂ will precipitate; Ba²⁺ and SO₄^{2 –} are spectator ions.
21. B) CuSO₄ will precipitate; Ba²⁺ and Cl ^– are spectator ions.
22. C) BaSO₄ will precipitate; Cu²⁺ and Cl^– are spectator ions.
23. D) BaCl₂ will precipitate; Cu²⁺ and SO₄^{2 –}  are spectator ions.
24. E) No precipitate will form.

Ans:  C     Category:  Medium     Section:  4.2

 

20. Based on the solubility rules, which of the following will occur when solutions of ZnSO₄(aq) and MgCl₂(aq) are mixed?
21. A) ZnCl₂ will precipitate; Mg²⁺ and SO₄^2–  will be spectator ions.
22. B) ZnSO₄ will precipitate; Mg²⁺ and Cl^– will be spectator ions.
23. C) MgSO₄ will precipitate; Zn²⁺ and Cl^– will be spectator ions.
24. D) MgCl₂ will precipitate; Zn²⁺ and SO₄^2– will be spectator ions.
25. E) No precipitate will form.

Ans:  E     Category:  Medium     Section:  4.2

 

21. Which of the following is the correct net ionic equation for the reaction that occurs when solutions of Pb(NO₃)₂ and NH₄Cl are mixed?
22. A) Pb(NO₃)₂(aq) + 2NH₄Cl(aq) ® NH₄NO₃(aq) + PbCl₂(s)
23. B) Pb²⁺(aq) + 2Cl^–(aq) ® PbCl₂(s)
24. C) Pb²⁺(aq) + 2NO₃^– (aq) + 2NH(aq) + 2Cl^–(aq) ® 2NH(aq) + 2NO₃^– (aq) + PbCl₂(s)
25. D) NH₄⁺(aq)+ NO₃^– (aq) ® 2NH₄NO₃(s)
26. E) No reaction occurs when the solutions are mixed.

Ans:  B     Category:  Medium     Section:  4.2

 

22. The common constituent in all acid solutions is
23. A) H₂.    B)  H⁺.    C)  OH^–.    D)  H₂SO₄.    E)  Cl^–.

Ans:  B     Category:  Easy     Section:  4.3

 

23. Which of the following compounds is a weak acid?
24. A) HF    B)  HCl    C)  HBr    D)  HI    E)  HClO₄

Ans:  A     Category:  Easy     Section:  4.1

 

24. Identify the major ions present in an aqueous LiOH solution.
25. A) Li²⁺,  O^– ,  H^–                                         D)      Li⁺,  O^2– ,  H⁺
26. B) Li⁺,  OH^–                                               E)      Li^– ,  OH⁺
27. C) LiO^–,  H⁺

Ans:  B     Category:  Easy     Section:  4.3

 

25. Identify the major ions present in an aqueous HNO₃  solution.
26. A) HN⁺,  O^2–                                              D)      H⁺,  N^3–,  O^2–
27. B) OH^– ,  NO₃^–                                           E)      H⁺,  NO₃^–
28. C) OH^– ,  NO

Ans:  E     Category:  Easy     Section:  4.3

 

26. Identify the major ionic species present in an aqueous solution of H₂SO₄.
27. A) S⁶⁺, O₃^6– (plus H₂O as a neutral species)
28. B) H⁺, OH^–, S⁶⁺, 3O^2–
29. C) 2H⁺, S⁶⁺, 4O^2–
30. D) H⁺, HSO₄^–
31. E) 2H⁺, SO₄^2–

Ans:  D     Category:  Medium     Section:  4.3

 

27. What is the correct formula of the salt formed in the neutralization reaction of hydrochloric acid with calcium hydroxide?
28. A) CaO    B)  CaCl₂    C)  CaH₂    D)  CaCl    E)  CaClH

Ans:  B     Category:  Medium     Section:  4.3

 

28. What is the chemical formula of the salt produced by the neutralization of hydrobromic acid with magnesium hydroxide?
29. A) MgBr    B)  Mg₂Br₃    C)  Mg₃Br₂    D)  Mg₂Br    E)  MgBr₂

Ans:  E     Category:  Medium     Section:  4.3

 

29. What is the chemical formula of the salt produced by the neutralization of nitric acid with calcium hydroxide?
30. A) CaNO₃    B)  Ca₂(NO₃)₃    C)  Ca₃(NO₃)₂    D)  Ca₂NO₃    E)  Ca(NO₃)₂

Ans:  E     Category:  Medium     Section:  4.3

 

30. What is the chemical formula of the salt produced by the complete neutralization of sodium hydroxide with sulfuric acid?
31. A) Na₂SO₄    B)  Na₂(SO₄)₃    C)  Na(SO₄)₂    D)  NaSO₃    E)  Na₃SO₄

Ans:  A     Category:  Medium     Section:  4.3

 

31. What is the chemical formula of the salt produced by the neutralization of potassium hydroxide with sulfuric acid?
32. A) KSO₃    B)  K₂(SO₄)₃    C)  K₂SO₄    D)  K(SO₄)₂    E)  KSO₄

Ans:  C     Category:  Medium     Section:  4.3

 

32. The oxidation number of N in NaNO₃ is
33. A) +6.    B)  +5.    C)  +3.    D)  –3.    E)  None of the above.

Ans:  B     Category:  Medium     Section:  4.4

 

33. The oxidation number of S in K₂SO₄ is
34. A) +6.    B)  +4.    C)  +2.    D)  –1.    E)  None of the above.

Ans:  A     Category:  Medium     Section:  4.4

 

34. The oxidation number of Mn in KMnO₄ is
35. A) +8.    B)  +7.    C)  +5.    D)  –7.    E)  –8.

Ans:  B     Category:  Medium     Section:  4.4

 

35. The oxidation number of Fe in K₃Fe(CN)₆ is
36. A) +3.    B)  +2.    C)  +1.    D)  –3.    E)  –4.

Ans:  A     Category:  Medium     Section:  4.4

 

36. The oxidation number of Cr in Cr₂O₇^2–  is
37. A) –12.    B)  –7.    C)  –2.    D)  +6.    E)  +7.

Ans:  D     Category:  Medium     Section:  4.4

 

37. The oxidation number of Cl in ClO₃^–  is
38. A) –1.    B)  +7.    C)  +5.    D)  +3.    E)  None of the above.

Ans:  C     Category:  Medium     Section:  4.4

 

38. The oxidation number of Cl in ClO₄^–   is
39. A) –1.    B)  +1.    C)  +3.    D)  +5.    E)  None of the above.

Ans:  E     Category:  Medium     Section:  4.4

 

39. The highest possible oxidation number of nitrogen is
40. A) +8.    B)  +5.    C)  +3.    D)  +1.    E)  –3.

Ans:  B     Category:  Medium     Section:  4.4

 

40. For which one of the following acids is chlorine in the +5 oxidation state?
41. A) HCl    B)  HClO    C)  HClO₂    D)  HClO₃    E)  HClO₄

Ans:  D     Category:  Medium     Section:  4.4

 

41. The highest possible oxidation number of carbon is
42. A) +8.    B)  +6.    C)  +4.    D)  +2.    E)  –4.

Ans:  C     Category:  Medium     Section:  4.4

 

42. Select the compound in which sulfur has its highest possible oxidation number.
43. A) H₂S    B)  SO₂    C)  SCl₂    D)  H₂SO₃    E)  Na₂SO₄

Ans:  E     Category:  Medium     Section:  4.4

 

43. The oxidation number of N in N₂H₄ is
44. A) +4.    B)  –4.    C)  +2.    D)  –2.    E)

Ans:  D     Category:  Medium     Section:  4.4

 

44. Which choice gives the correct oxidation numbers for all three elements in Rb₂SO₃ in the order that the elements are shown in the formula?
45. A) –2, +6, –2    B)  –1, +4, –3    C)  +2, +4, –2    D)  +1, +4, –2    E)  +1, +6, –6

Ans:  D     Category:  Medium     Section:  4.4

 

45. Which choice gives the correct oxidation numbers for all three elements in Ca(ClO)₂ in the order that the elements are shown in the formula?
46. A) +2, +1, –2    B)  +2, –2, +1    C)  +2, –3, +2    D)  –2, +2, –1    E)  –2, +3, –2

Ans:  A     Category:  Medium     Section:  4.4

 

46. In the following redox reaction

4NH₃ + 3Ca(ClO)₂ ® 2N₂ + 6H₂O + 3CaCl₂

which element is oxidized and which is reduced?

1. A) H is oxidized and N is reduced            D)      Cl is oxidized and O is reduced
2. B) N is oxidized and Cl is reduced            E)      Cl is oxidized and N is reduced
3. C) N is oxidized and O is reduced

Ans:  B     Category:  Medium     Section:  4.4

 

47. Which one of the following is a redox reaction?
48. A) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)
49. B) 2KBr(aq) + Pb(NO₃)₂(aq) ® 2KNO₃(aq) + PbBr₂(s)
50. C) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)
51. D) H⁺(aq) + OH^– (aq) ® H₂O(l)
52. E) CO₃^2– (aq) + HSO₄^–(aq) ® HCO₃^– (aq) + SO₄^2– (aq)

Ans:  A     Category:  Medium     Section:  4.4

 

48. Which of the following equations does not represent an oxidation-reduction reaction?
49. A) 3Al + 6HCl ® 3H₂ + AlCl₃
50. B) 2H₂O ® 2H₂ + O₂
51. C) 2NaCl + Pb(NO₃)₂ ® PbCl₂ + 3NaNO₃
52. D) 2NaI + Br₂ ® 2NaBr + I₂
53. E) Cu(NO₃)₂ + Zn ® Zn(NO₃)₂ + Cu

Ans:  C     Category:  Medium     Section:  4.4

 

49. In the following chemical reaction the oxidizing agent is:

5H₂O₂ + 2MnO₄^–  + 6H⁺ ® 2Mn²⁺ + 8H₂O + 5O₂

1. A) H₂O₂    B)  MnO₄^–    C)  H⁺    D)  Mn²⁺    E)  O₂

Ans:  B     Category:  Difficult     Section:  4.4

 

50. In the following chemical reaction the oxidizing agent is:

5S + 6KNO₃ + 2CaCO₃ ® 3K₂SO₄ + 2CaSO₄ + CO₂ + 3N₂

1. A) S    B)  N₂    C)  KNO₃    D)  CaSO₄    E)  CaCO₃

Ans:  C     Category:  Difficult     Section:  4.4

 

51. Identify the oxidizing agent in the following chemical reaction.

2MnO₄^–   + 5H₂SO₃  ®  2Mn²⁺ + 5SO₄^2–   + 4H⁺ + 3H₂O

1. A) MnO₄^–    B)  H₂SO₃    C)  Mn²⁺    D)  SO₄^2–    E)  H⁺

Ans:  A     Category:  Difficult     Section:  4.4

 

52. Identify the reducing agent in the following chemical reaction.

5Fe²⁺(aq) + MnO₄^–(aq)  + 8H⁺(aq) ® 5Fe³⁺(aq) + Mn²⁺(aq) + 4H₂O(l)

1. A) Fe²⁺    B)  MnO₄^–    C)  H⁺    D)  Mn²⁺    E)  Fe³⁺

Ans:  A     Category:  Difficult     Section:  4.4

 

53. Identify the reducing agent in the following chemical reaction.

Cd + NiO₂ + 2H₂O ® Cd(OH)₂ + Ni(OH)₂

1. A) Cd    B)  NiO₂    C)  H₂O    D)  Cd(OH)₂    E)  Ni(OH)₂

Ans:  A     Category:  Difficult     Section:  4.4

 

54. What element is oxidized in the following chemical reaction?

3Cu + 8HNO₃ ® 3Cu(NO₃)₂ + 2NO + 4H₂O

1. A) Cu    B)  H    C)  N    D)  O    E)  H₂O

Ans:  A     Category:  Medium     Section:  4.4

 

55. What element is oxidized in the following chemical reaction?

NiO₂ + Cd + 2H₂O ®  Ni(OH)₂ + Cd(OH)₂

1. A) Ni    B)  Cd    C)  O    D)  H    E)  This is not a redox reaction.

Ans:  B     Category:  Medium     Section:  4.4

 

56. What element is oxidized in the following chemical reaction?

H₂SO₄ + Cd(OH)₂ ® 2H₂O + CdSO₄

1. A) H    B)  S    C)  O    D)  Cd    E)  this is not a redox reaction

Ans:  E     Category:  Medium     Section:  4.4

 

57. What element is reduced in the following chemical reaction?

Cu + 2H₂SO₄ ® CuSO₄ + SO₂ + 2H₂O

1. A) Cu    B)  H    C)  S    D)  O    E)  H₂O

Ans:  C     Category:  Medium     Section:  4.4

 

58. Identify the elements that are oxidized and reduced in the following reaction.

KClO₃(aq)  +  6HBr(aq)  ®  KCl(aq)  +  3Br₂(l)  +  3H₂O(l)

1. A) Br is oxidized and Cl is reduced           D)      O is oxidized and Cl is reduced
2. B) Cl is oxidized and H is reduced            E)      Cl is oxidized and Br is reduced
3. C) H is oxidized and O is reduced

Ans:  A     Category:  Medium     Section:  4.4

 

59. Predict the products of the following single replacement reaction.

Fe(s) + CuSO₄(aq) ®

1. A) Cu(s) + FeSO₄(aq)                                 D)      FeCuSO₄(aq)
2. B) Fe(s) + Cu(s) + SO₄(aq)                        E)      FeO(s) + CuSO₃(aq)
3. C) CuS(s) + Fe₂SO₄(aq)

Ans:  A     Category:  Medium     Section:  4.4

 

60. Which of the following is an example of a disproportionation reaction?
61. A) 2C₂H₆(g) + 7O₂(g) ® 4CO₂(g) + 6H₂O(l)
62. B) 2KBr(aq) + Cl₂(g) ® 2KCl(aq) + Br₂(l)
63. C) 2H₂O₂(aq) ® 2H₂O(l) + O₂(g)
64. D) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)
65. E) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)

Ans:  C     Category:  Medium     Section:  4.4

 

61. Which of the following represents a metal displacement reaction?
62. A) 2NaN₃(s) ® 2Na(s) + 3N₂(g)
63. B) Fe₂O₃(s) + 2Al(s) ® 2Fe(s) + Al₂O₃(s)
64. C) 3NO₂(g) + H₂O(l) ® 2HNO₃(aq) + NO(g)
65. D) 2P(s) + 3Cl₂(g) ® 2PCl₃(g)
66. E) 2ZnS(s) + 3O₂(g) ® 2ZnO(s) + 2SO₂(g)

Ans:  B     Category:  Easy     Section:  4.4

 

62. Which of the following represents a halogen displacement reaction?
63. A) 2KBr(aq) + Cl₂(g) ® 2KCl(aq) + Br₂(l)
64. B) 2Na(s) + 2H₂O(l) ® 2NaOH(aq) + H₂(g)
65. C) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)
66. D) 2KNO₃(s) ® 2KNO₂(s) + O₂(g)
67. E) 2LiOH(aq) + H₂SO₄(aq) ® Li₂SO₄(aq) + 2H₂O(l)

Ans:  A     Category:  Easy     Section:  4.4

 

63. Which of the following represents a precipitation reaction?
64. A) 2H₂(g) + O₂(g) ® 2H₂O(l)
65. B) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)
66. C) 2KNO₃(s) ® 2KNO₂(s) + O₂(g)
67. D) 2KBr(aq) + Cl₂(g) ® 2KCl(aq) + Br₂(l)
68. E) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)

Ans:  B     Category:  Easy     Section:  4.2

 

64. Which of the following represents an acid-base neutralization reaction?
65. A) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)
66. B) SO₂(g) + H₂O(l) ® H₂SO₃(g)
67. C) LiOH(aq) + HNO₃(aq) ® LiNO₃(aq) + H₂O(l)
68. D) 2KBr(aq) + Cl₂(g) ® 2KCl(aq) + Br₂(l)
69. E) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)

Ans:  C     Category:  Medium     Section:  4.4

 

65. Which of the following represents a hydrogen displacement reaction?
66. A) 2C₂H₆(g) + 7O₂(g) ® 4CO₂(g) + 6H₂O(l)
67. B) 2KBr(aq) + Cl₂(g) ® 2KCl(aq) + Br₂(l)
68. C) N₂(g) + 3H₂(g) ® 2NH₃(g)
69. D) CaBr₂(aq) + H₂SO₄(aq) ® CaSO₄(s) + 2HBr(g)
70. E) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)

Ans:  E     Category:  Medium     Section:  4.4

 

66. Which of the following represents a combustion reaction?
67. A) 2C₂H₆(g) + 7O₂(g) ® 4CO₂(g) + 6H₂O(l)
68. B) LiOH(aq) + HNO₃(aq) ® LiNO₃(aq) + H₂O(l)
69. C) N₂(g) + 3H₂(g) ® 2NH₃(g)
70. D) 2Na(s) + 2H₂O(l) ® 2NaOH(aq) + H₂(g)
71. E) 2Al(s) + 3H₂SO₄(aq) ® Al₂(SO₄)₃(aq) + 3H₂(g)

Ans:  A     Category:  Easy     Section:  4.4

 

67. What mass of K₂CO₃ is needed to prepare 200. mL of a solution having a potassium ion concentration of 0.150 M?
68. A) 15 g    B)  10.4 g    C)  13.8 g    D)  2.07 g    E)  1.49 g

Ans:  D     Category:  Medium     Section:  4.5

 

68. What mass of Na₂SO₄ is needed to prepare 350. mL of a solution having a sodium ion   concentration of 0.125 M?
69. A) 11 g    B)  24.9 g    C)  12.4 g    D)  6.21 g    E)  8.88 g

Ans:  A     Category:  Medium     Section:  4.5

 

69. What mass of Li₃PO₄ is needed to prepare 500. mL of a solution having a lithium ion concentration of 0.175 M?
70. A) 75 g    B)  10.1 g    C)  19.3 g    D)  30.4 g    E)  3.38 g

Ans:  E     Category:  Medium     Section:  4.5

 

70. A 50.0 mL sample of 0.436 M NH₄NO₃ is diluted with water to a total volume of 250.0 mL.  What is the ammonium nitrate concentration in the resulting solution?
71. A) 8 M    B)  0.459 M    C)  2.18 ´ 10^–2 M    D)  8.72 ´ 10^–2 M    E)  0.109 M

Ans:  D     Category:  Medium     Section:  4.5

 

71. A 20.00 mL sample of 0.1015 M nitric acid is introduced into a flask, and water is added until the volume of the solution reaches 250. mL.  What is the concentration of nitric acid in the final solution?
72. A) 27 M                                                   D)      3.25 ´ 10^–2 M
73. B) 12 ´ 10^–3 M                                        E)      5.08 ´ 10^–4 M
74. C) 406 M

Ans:  B     Category:  Medium     Section:  4.5

 

72. A 3.682 g sample of KClO₃ is dissolved in enough water to give 375. mL of solution. What is the chlorate ion concentration in this solution?
73. A) 00 ´ 10^–2 M                                        D)      1.65 ´ 10^–2 M
74. B) 41 ´ 10^–2 M                                        E)      8.01 ´ 10^–2 M
75. C) 118 M

Ans:  E     Category:  Medium     Section:  4.5

 

73. A 4.691 g sample of MgCl₂ is dissolved in enough water to give 750. mL of solution. What is the magnesium ion concentration in this solution?
74. A) 70 ´ 10^–2 M                                        D)      4.93 ´ 10^–2 M
75. B) 05 ´ 10^–2 M                                        E)      0.131 M
76. C) 57 ´ 10^–2 M

Ans:  C     Category:  Medium     Section:  4.5

 

74. A 0.9182 g sample of CaBr₂ is dissolved in enough water to give 500. mL of solution. What is the calcium ion concentration in this solution?
75. A) 19 ´ 10^–3 M                                        D)      4.59 ´ 10^–3 M
76. B) 30 ´ 10^–3 M                                        E)      1.25 ´ 10^–3 M
77. C) 72 ´ 10^–3 M

Ans:  A     Category:  Medium     Section:  4.5

 

75. 35.0 mL of 0.255 M nitric acid is added to 45.0 mL of 0.328 M Mg(NO₃)₂.  What is the concentration of nitrate ion in the final solution?
76. A) 481 M    B)  0.296 M    C)  0.854 M    D)  1.10 M    E)  0.0295 M

Ans:  A     Category:  Difficult     Section:  4.5

 

76. 17.5 mL of a 0.1050 M Na₂CO₃ solution is added to 46.0 mL of 0.1250 M NaCl.  What is the concentration of sodium ion in the final solution?
77. A) 205 M    B)  0.119 M    C)  0.539 M    D)  0.148 M    E)  0.165 M

Ans:  D     Category:  Difficult     Section:  4.5

 

77. 25.0 mL of a 0.2450 M NH₄Cl solution is added to 55.5 mL of 0.1655 M FeCl₃.  What is the concentration of chloride ion in the final solution?
78. A) 607 M    B)  0.418 M    C)  1.35 M    D)  0.190 M    E)  0.276 M

Ans:  B     Category:  Difficult     Section:  4.5

 

78. When 38.0 mL of 0.1250 M H₂SO₄ is added to 100. mL of a solution of PbI₂, a precipitate of PbSO₄ forms.  The PbSO₄ is then filtered from the solution, dried, and weighed.  If the recovered PbSO₄ is found to have a mass of 0.0471 g, what was the concentration of iodide ions in the original solution?
79. A) 10 ´ 10^–4 M                                        D)      3.11 ´ 10^–3 M
80. B) 55 ´ 10^–4 M                                        E)      1.55 ´ 10^–3 M
81. C) 20 ´ 10^–3 M

Ans:  D     Category:  Difficult     Section:  4.6

 

79. When 50.0 mL of a 0.3000 M AgNO₃ solution is added to 50.0 mL of a solution of MgCl₂, an AgCl precipitate forms immediately.  The precipitate is then filtered from the solution, dried, and weighed.  If the recovered AgCl is found to have a mass of 0.1183 g, what is the concentration of magnesium ions in the original MgCl₂ solution?
80. A) 300 M                                                 D)      2.06 ´ 10^–5 M
81. B) 25 ´ 10^–3 M                                        E)      4.13 ´ 10^–3 M
82. C) 65 ´ 10^–2 M

Ans:  B     Category:  Difficult     Section:  4.6

 

80. When 20.0 mL of a 0.250 M (NH₄)₂S solution is added to 150.0 mL of a solution of Cu(NO₃)₂, a CuS precipitate forms.  The precipitate is then filtered from the solution, dried, and weighed.  If the recovered CuS is found to have a mass of 0.3491 g, what was the concentration of copper ions in the original Cu(NO₃)₂ solution?
81. A) 65 ´ 10^–3 M                                        D)      4.87 ´ 10^–2 M
82. B) 22 ´ 10^–2 M                                        E)      2.43 ´ 10^–2 M
83. C) 33 ´ 10^–2 M

Ans:  E     Category:  Difficult     Section:  4.6

 

81. 34.62 mL of 0.1510 M NaOH was needed to neutralize 50.0 mL of an H₂SO₄ solution.  What is the concentration of the original sulfuric acid solution?
82. A) 0229 M    B)  0.218 M    C)  0.0523 M    D)  0.209 M    E)  0.105 M

Ans:  C     Category:  Medium     Section:  4.7

 

82. When solid iron(II) hydroxide is added to water, the resulting solution contains 1.4 ´ 10^–3g of dissolved iron(II) hydroxide per liter of solution.  What is the hydroxide ion concentration in this solution?
83. A) 8 ´ 10^–6 M                                          D)      3.1 ´ 10^–5 M
84. B) 6 ´ 10^–5 M                                          E)      4.0 ´ 10^–3 M
85. C) 5 ´ 10^–10 M

Ans:  D     Category:  Difficult     Section:  4.5

 

83. A 250. mL sample of 0.0328M HCl is partially neutralized by the addition of 100. mL of 0.0245M NaOH.  Find the concentration of hydrochloric acid in the resulting solution.
84. A) 00700 M    B)  0.0164 M    C)  0.0383 M    D)  0.0230 M    E)  0.0575 M

Ans:  B     Category:  Difficult     Section:  4.7

 

84. A 350. mL sample of 0.276M HNO₃ is partially neutralized by 125 mL of 0.0120M Ca(OH)₂.  Find the concentration of nitric acid in the resulting solution.
85. A) 210 M    B)  0.00632 M    C)  0.203 M    D)  0.0240 M    E)  0.197 M

Ans:  E     Category:  Difficult     Section:  4.7

 

85. 158 mL of a 0.148M NaCl solution is added to 228 mL of a 0.369M NH₄NO₃ solution.  The concentration of ammonium ions in the resulting mixture is
86. A) 157 M.    B)  0.218 M.    C)  0.625 M.    D)  0.369 M.    E)  0 M.

Ans:  B     Category:  Medium     Section:  4.5

 

86. 1.40 g of silver nitrate is dissolved in 125 mL of water.  To this solution is added 5.00 mL of 1.50M hydrochloric acid, and a precipitate forms.  Find the concentration of silver ions remaining in solution.
87. A) 7 ´ 10^–3 M                                          D)      0.121M
88. B) 34 ´ 10^–2 M                                        E)      5.9 ´ 10^–3 M
89. C) 77 ´ 10^–2 M

Ans:  A     Category:  Difficult     Section:  4.6

 

87. Calcium sulfate dihydrate (commonly known as gypsum) dissolves in cold water to the extent of 0.241 g per 100. cm³.  What is the concentration of calcium ions in this solution?
88. A) 77 ´ 10^–2 M                                        D)      3.54 ´ 10^–2 M
89. B) 80 ´ 10^–2 M                                        E)      1.40 ´ 10^–2 M
90. C) 77 ´ 10^–3 M

Ans:  E     Category:  Difficult     Section:  4.5

 

88. Calcium nitrate tetrahydrate dissolves in cold water to the extent of 266 g per 100. cm³.  What is the concentration of nitrate ions in this solution?
89. A) 4M    B)  22.5M    C)  11.3M    D)  16.2M    E)  8.10M

Ans:  B     Category:  Difficult     Section:  4.5

 

89. Define solution, solute, and solvent.

Ans:  A solution is a homogeneous mixture of two or more substances.  The substance present in a smaller amount is called the solute, while the substance present in the larger amount is called the solvent.

Category:  Easy     Section:  4.1

 

90. Identify the following compound as an electrolyte or nonelectrolyte: NaOH.

Ans:  electrolyte

Category:  Easy     Section:  4.1

 

91. Identify the following compound as an electrolyte or nonelectrolyte: H₂SO₄.

Ans:  electrolyte

Category:  Easy     Section:  4.1

 

92. Identify the following compound as an electrolyte or nonelectrolyte: Methanol (CH₃OH).

Ans:  nonelectrolyte

Category:  Easy     Section:  4.1

 

93. Identify the following compound as an electrolyte or nonelectrolyte: C₁₂H₂₂O₁₁(sucrose).

Ans:  nonelectrolyte

Category:  Easy     Section:  4.1

 

94. Identify the following compound as an electrolyte or nonelectrolyte: MgCl₂.

Ans:  electrolyte

Category:  Easy     Section:  4.1

 

95. Identify the following compound as a strong electrolyte, weak electrolyte, or nonelectrolyte: CH₃OH (methanol).

Ans:  nonelectrolyte

Category:  Easy     Section:  4.1

 

96. Identify the following compound as a strong electrolyte, weak electrolyte, or nonelectrolyte: CH₃COOH.

Ans:  weak electrolyte

Category:  Easy     Section:  4.1

 

97. Identify the following compounds as a strong electrolytes, weak electrolytes, or nonelectrolytes: KNO₃, KNO₂, HNO₃, HNO₂,

Ans:  KNO₃, KNO₂, and HNO₃ are strong electrolytes; HNO₂ is a weak electrolyte.

Category:  Medium     Section:  4.3

 

98. Identify the following compound as a strong electrolyte, weak electrolyte, or nonelectrolyte: NH₃.

Ans:  weak electrolyte

Category:  Medium     Section:  4.1

 

99. Identify the following compound as a strong electrolyte, weak electrolyte, or nonelectrolyte: NH₄Cl.

Ans:  strong electrolyte

Category:  Easy     Section:  4.1

 

100. Define and illustrate with an example the difference between an electrolyte and a nonelectrolyte.

Ans:  (Answers will vary.) An electrolyte is a substance that, when dissolved in water, results in a solution that can conduct electricity. An example is sodium hydrogen carbonate. A nonelectrolyte does not conduct electricity when dissolved in water. An example would be sugar.

Category:  Medium     Section:  4.1

 

101. Define precipitate and illustrate with an example.

Ans:  (Answers will vary.) A precipitate is an insoluble solid that separates from a solution.

CoCl₂ (aq)  +  Na₂CO₃(aq)  ®  CoCO₃ (s) +  2NaCl (aq)

In this reaction, CoCO₃ is a precipitate.

Category:  Medium     Section:  4.2

 

102. Give an example of a monoprotic acid.

Ans:  HNO₃ (for example)

Category:  Easy     Section:  4.3

 

103. Give an example of a diprotic acid.

Ans:  H₂CO₃ (for example)

Category:  Easy     Section:  4.3

 

104. Name and give the formulas for six strong acids.

Ans:  hydrochloric acid, HCl; hydrobromic acid, HBr; hydroiodic acid, HI; nitric acid, HNO₃; sulfuric acid, H₂SO₄; perchloric acid, HClO₄

Category:  Easy     Section:  4.3

 

105. Give an example of a triprotic acid.

Ans:  H₃PO₄

Category:  Easy     Section:  4.3

 

106. Write the net ionic equation for the following reaction. Aqueous iron(III) sulfate is added to aqueous sodium sulfide to produce solid iron(III) sulfide and aqueous sodium sulfate.

Ans:  2Fe³⁺(aq)  +  3S^{2 –} (aq)  ®  Fe₂S₃(s)

Category:  Medium     Section:  4.2

 

107. Determine the oxidation number of each of the elements in Cs₂Cr₂O₇?

Ans:  the oxidation number of Cs is +1; the oxidation number of Cr is +6; the oxidation number of O is –2

Category:  Easy     Section:  4.4

 

108. Identify the element being oxidized in the following reaction.

4Al  + 3O₂  ® 2Al₂O₃

Ans:  Al

Category:  Medium     Section:  4.4

 

109. Identify the element being reduced in the following reaction.

4Al  + 3O₂  ® 2Al₂O₃

Ans:  O

Category:  Medium     Section:  4.4

 

110. Identify the oxidizing agent in the following reaction.

4Al  + 3O₂  ® 2Al₂O₃

Ans:  O₂

Category:  Medium     Section:  4.4

 

111. Identify the reducing agent in the following reaction.

4Al  + 3O₂  ® 2Al₂O₃

Ans:  Al

Category:  Medium     Section:  4.4

 

112. Identify the element being oxidized in the following reaction.

2KBr + F₂ ®  Br₂ + 2KF

Ans:  Br

Category:  Medium     Section:  4.4

 

113. Identify the element being reduced in the following reaction.

2KBr + F₂ ®  Br₂ + 2KF

Ans:  F

Category:  Medium     Section:  4.4

 

114. Identify the oxidizing agent in the following reaction.

2KBr + F₂ ®  Br₂ + 2KF

Ans:  F₂

Category:  Medium     Section:  4.4

 

115. Identify the reducing agent in the following reaction.

2KBr + F₂ ®  Br₂ + 2KF

Ans:  Br^– (or KBr)

Category:  Medium     Section:  4.4

 

116. Determine the oxidation number of each of the elements BaNaPO₄?

Ans:  the oxidation number of Ba +2; the oxidation number of Na is +1; the oxidation number of P is +5; the oxidation number of O is –2

Category:  Easy     Section:  4.4

 

117. Determine the oxidation number of each of the elements in K₂TaF₇?

Ans:  the oxidation number of K is +1; the oxidation number of Ta is +5; the oxidation number of F is –1

Category:  Easy     Section:  4.4

 

118. Thorium metal is prepared by reacting thorium oxide with calcium.

ThO₂ + 2Ca ® Th + 2CaO

Which substance is reduced in this process?

Ans:  Th⁴⁺ is reduced

Category:  Medium     Section:  4.4

 

119. Thorium metal is prepared by reacting thorium oxide with calcium.

ThO₂ + 2Ca ® Th + 2CaO

What is the reducing agent in this process?

Ans:  Ca

Category:  Medium     Section:  4.4

 

120. Thorium metal is prepared by reacting thorium oxide with calcium.

ThO₂ + 2Ca ® Th + 2CaO

Which substance is oxidized in this process?

Ans:  Ca

Category:  Medium     Section:  4.4

 

121. Thorium metal is prepared by reacting thorium oxide with calcium.

ThO₂ + 2Ca ® Th + 2CaO

What is the oxidizing agent in this process?

Ans:  ThO₄

Category:  Medium     Section:  4.4

 

122. Batteries in our cars generate electricity by the following chemical reaction.

Pb + PbO₂ + 2H₂SO₄ ® 2PbSO₄ + 2H₂O

Which substance is reduced in this process?

Ans:  Pb⁴⁺

Category:  Medium     Section:  4.4

 

123. Batteries in our cars generate electricity by the following chemical reaction.

Pb + PbO₂ + 2H₂SO₄ ® 2PbSO₄ + 2H₂O

What is the reducing agent in this process?

Ans:  Pb

Category:  Medium

 

124. Batteries in our cars generate electricity by the following chemical reaction.

Pb + PbO₂ + 2H₂SO₄ ® 2PbSO₄ + 2H₂O

Which substance is oxidized in this process?

Ans:  Pb

Category:  Medium     Section:  4.4

 

125. Batteries in our cars generate electricity by the following chemical reaction.

Pb + PbO₂ + 2H₂SO₄ ® 2PbSO₄ + 2H₂O

What is the oxidizing agent in this process?

Ans:  PbO₂

Category:  Medium     Section:  4.4

 

126. Describe the procedure used to make 3.0 liters of a 2.0 M KCl solution, starting with solid KCl and water.

Ans:  Determine the molar mass of KCl, which is 74.55 g/mol; weigh out 447.3 grams (6 mol) of KCl; dissolve the KCl in enough water to form exactly 3 liters of solution.

Category:  Medium     Section:  4.5

 

127. What is the molarity of a solution that contains 5.0 moles of solute in 2.00 liters of solution?

Ans:  2.5 M

Category:  Easy     Section:  4.5

 

128. The solubility of Ba(NO₃)₂ is 130.5 grams per liter at 0°C.  How many moles of dissolved salt are present in 4.0 liters of a saturated solution of Ba(NO₃)₂ at 0ºC?

Ans:  2.0 moles

Category:  Medium     Section:  4.5

 

129. What is the molar concentration of chloride ions in a solution prepared by mixing 100. mL of 2.0 M KCl with 50. mL of a 1.5 M CaCl₂ solution?

Ans:  2.3 M

Category:  Difficult

 

130. What volume of concentrated nitric acid (15.0 M) is required to make 100. mL of a 3.0 M nitric acid solution?

Ans:  20. mL

Category:  Medium     Section:  4.5

 

131. During a titration the following data were collected. A 10. mL portion of an unknown monoprotic acid solution was titrated with 1.0 M NaOH; 40. mL of the base were required to neutralize the sample.  What is the molarity of the acid solution?

Ans:  4.0 M

Category:  Medium     Section:  4.7

 

132. During a titration the following data were collected. A 10. mL portion of an unknown monoprotic acid solution was titrated with 1.0 M NaOH; 40. mL of the base were required to neutralize the sample.  How many moles of acid are present in 2.0 liters of this unknown solution?

Ans:  8.0 moles

Category:  Medium     Section:  4.7

 

133. If 145 grams of potassium nitrate were added to water to make 1,500 mL of solution, what would be the molarity of the resulting solution?

Ans:  0.956 M

Category:  Medium     Section:  4.5

 

134. During a titration the following data were collected. A 50.0 mL portion of an HCl solution was titrated with 0.500 M NaOH; 200. mL of the base was required to neutralize the sample. How many grams of HCl are present in 500. mL of this acid solution?

Ans:  36.5 g

Category:  Medium     Section:  4.7

 

135. Identify the following as either a good or poor conductor of electricity: a crystal of Na₂SO₄.

Ans:  poor

Category:  Easy     Section:  4.1

 

136. Identify the following as either a good or poor conductor of electricity: an aqueous solution of Na₂SO₄.

Ans:  good

Category:  Easy     Section:  4.1

 

137. Identify the following as either a good or poor conductor of electricity: gasoline (C₈H₁₈).

Ans:  poor

Category:  Easy     Section:  4.1

 

138. Which substance is acting as a Brønsted acid in the following reaction?

HSO₄^– + NH₄⁺ ® H₂SO₄ + NH₃

Ans:  NH₄⁺

Category:  Medium     Section:  4.3

 

139. Identify the Brønsted acid in the following reaction.

NH₃  +  H₂O ® NH₄⁺ + OH^–

Ans:  H₂O

Category:  Medium     Section:  4.3

 

140. Write balanced molecular and net ionic equations for the reaction that would occur between CaCl₂(aq) and Na₂CO₃(aq). Be sure to include the correct states in your final equations. If no reaction is expected, write “no reaction.”

Ans:  Molecular equation:  CaCl₂(aq)  +  Na₂CO₃(aq)  ®  CaCO₃(s)  +  2NaCl(aq)

Net ionic equation:  Ca²⁺(aq)  +  CO₃^2–(aq)  ®  CaCO₃(s)

Category:  Medium     Section:  4.2

 

141. Write balanced molecular and net ionic equations for the acid-base neutralization reaction between H₃PO₄(aq) and Ba(OH)₂(aq). Be sure to include the correct states in your final equations. If no reaction is expected, write “no reaction.”

Ans:  Molecular equation:  2H₃PO₄(aq)  +  3Ba(OH)₂(aq)  ®  Ba₃(PO₄)₂(s)  +  6H₂O(l)

Net ionic equation: 2H₃PO₄(aq)  +  3Ba²⁺(aq)  +  6OH^–(aq)  ®  Ba₃(PO₄)₂(s)  +  6H₂O(l)

Category:  Difficult     Section:  4.3

 

142. Write balanced molecular and net ionic equations for the reaction that would occur between Al(s) and Co(NO₃)₂(aq). Be sure to include the correct states in your final equations. If no reaction is expected, write “no reaction.”

Ans:  Molecular equation:  2Al(s)  +  3Co(NO₃)₂(aq)  ®  2Al(NO₃)₃(aq)  +  3Co(s)

Net ionic equation:  2Al(s)  +  3Co²⁺(aq)  ®  2Al³⁺(aq)  +  3Co(s)

Category:  Medium     Section:  4.4

 

143. Write balanced molecular and net ionic equations for the reaction that would occur between CuCl₂(aq) and Pb(s). Be sure to include the correct states in your final equations. If no reaction is expected, write “no reaction.”

Ans:  Molecular equation:  CuCl₂(aq)  +  Pb(s)  ®  Cu(s)  +  PbCl₂(s)

Net ionic equation:  Cu²⁺(aq)  +  2Cl^–(aq)  +  Pb(s)  ®  Cu(s)  +  PbCl₂(s)

Category:  Difficult     Section:  4.4

 

144. A piece of copper metal was added to an aqueous solution of silver nitrate, and within a few minutes it was observed that a grey crystalline solid formed on surface of the copper and the solution turned a blue color characteristic of copper(II) ions.

Write the balanced chemical equation for this reaction.

Ans:  Cu(s) + 2AgNO₃(aq)  ®  2Ag(s) + Cu(NO₃)₂(aq)

Category:  Medium     Section:  4.4

 

145. A piece of copper metal was added to an aqueous solution of silver nitrate, and within a few minutes it was observed that a grey crystalline solid formed on surface of the copper and the solution turned a blue color characteristic of copper(II) ions.

Write the net ionic equation for this reaction.

Ans:  Cu(s) + 2Ag⁺(aq) ® Cu²⁺(aq) + 2Ag(s)

Category:  Medium     Section:  4.4

 

146. A piece of lead metal was added to an aqueous solution of copper(II) nitrate, and within a few minutes it was observed that the lead turned black and crumbled, and the blue solution  characteristic of copper(II) ions faded. (NOTE:  Lead forms a 2+ ion when it reacts.)

Write the balanced chemical equation for this reaction.

Ans:  Pb(s)  + Cu(NO₃)₂(aq)   ®  Cu(s)   +  Pb(NO₃)₂(aq)

Category:  Medium     Section:  4.4

 

147. A piece of lead metal was added to an aqueous solution of copper(II) nitrate, and within a few minutes it was observed that the lead turned black and crumbled, and the blue solution  characteristic of copper(II) ions faded. (NOTE:  Lead forms a 2+ ion when it reacts.)

Write the net ionic equation for this reaction.

Ans:  Pb(s) + Cu²⁺(aq) ® Pb²⁺(aq) + Cu(s)

Category:  Medium     Section:  4.4

 

148. A piece of zinc metal was added to an aqueous solution of lead(II) nitrate. After some time it was observed that the zinc metal had appeared to fall apart and a solid had accumulated at the bottom of the reaction vessel.

Write the balanced chemical equation for this reaction.

Ans:  Zn(s) + Pb(NO₃)₂(aq)  ® Pb(s) + Zn(NO₃)₂(aq)

Category:  Difficult     Section:  4.4

 

149. A piece of zinc metal was added to an aqueous solution of lead(II) nitrate. After some time it was observed that the zinc metal had appeared to fall apart and a solid had accumulated at the bottom of the reaction vessel.

Write the net ionic equation for this reaction.

Ans:  Zn(s) + Pb²⁺(aq) ® Zn²⁺(aq) + Pb(s)

Category:  Difficult     Section:  4.4

 

150. The following experiments were carried out and observations recorded.

 

Expt. #1:  copper metal was added to an aqueous solution of silver nitrate

Observation:  The copper become coated with a substance.

Expt. #2:  lead metal was added to an aqueous solution of copper(II) nitrate

Observation:  The lead turned black and crumbled.

Expt. #3:  zinc metal was added to an aqueous solution of lead(II) nitrate

Observation:  The zinc appeared to fall apart.

 

Rank the metals from most active to least active.

Ans:  most active Zn, next most active Pb, next most active Cu, least active Ag

Category:  Difficult     Section:  4.4

 

151. Write a balanced molecular equation for the reaction that occurs when aqueous solutions of potassium iodide and lead(II) nitrate are combined.

Ans:  2KI(aq)  +  Pb(NO₃)₂(aq)  ®  PbI₂(s)  +  2KNO₃(aq)

Category:  Medium     Section:  4.2

 

152. If 73.5 mL of 0.200 M KI(aq) was required to precipitate all of the lead(II) ion from an aqueous solution of lead(II) nitrate, how many moles of Pb²⁺ were originally in the solution?

Ans:  7.35 ´ 10^–3 moles of  Pb²⁺

Category:  Medium     Section:  4.6

 

153. Sugar dissolves in water, therefore it is a strong electrolyte.

Ans:  False     Category:  Medium     Section:  4.1

 

154. Silver chloride (AgCl) has an extremely low solubility in water; therefore, it is a weak electrolyte.

Ans:  False     Category:  Medium     Section:  4.1

 

155. Most compounds containing chlorides, bromides, and iodides are soluble except those containing Ag⁺, Hg₂²⁺, and Pb²⁺.

Ans:  True     Category:  Easy     Section:  4.2

 

156. The following reaction is an acid-base neutralization reaction.

H₂SO₄(aq) + CaBr₂(aq) ® CaSO₄(s) + 2HBr(g)

Ans:  False     Category:  Easy     Section:  4.3

 

157. The oxidation number of N in NO is +7.

Ans:  False     Category:  Easy     Section:  4.4

 

158. Hydrogen is oxidized in the following chemical reaction.

H₂ + Cl₂ ® 2HCl

Ans:  True     Category:  Medium     Section:  4.4

 

159. The following equation is an example of a net ionic equation.

Na⁺(aq) + Br^–(aq)  + Ag⁺(aq) + NO₃^–(aq)  ®  AgBr(s) + Na⁺(aq) + NO₃^–(aq)

Ans:  False     Category:  Medium     Section:  4.2

 

160. The oxidation number of iodine increases by 6 in the following reaction.

2MnO₄^–   + I ^–  + H₂O ® 2MnO₂ + IO₃^–   + 2OH^–

Ans:  True     Category:  Medium     Section:  4.4

 

161. A weak acid or a weak base ionizes completely.

Ans:  False     Category:  Medium     Section:  4.3

 

162. The following reaction is a redox reaction.

CaC₂(s)  +  H₂O(l)  ®  HCCH(g)  +  CaO(s)

Ans:  False     Category:  Medium     Section:  4.4