General Organic And Biological Chemistry 2nd Edition By Laura D. Frost- Test Bank

General Organic And Biological Chemistry 2nd Edition By Laura D. Frost- Test Bank   Instant Download - Complete Test Bank With Answers     Sample Questions Are Posted Below   Chapter 5: Chemical Reactions   1. The law of conservation of mass states that   A) Atoms cannot be created or destroyed in a chemical …

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General Organic And Biological Chemistry 2nd Edition By Laura D. Frost- Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Chapter 5: Chemical Reactions

 

1. The law of conservation of mass states that
  A) Atoms cannot be created or destroyed in a chemical reaction.
  B) Molecules cannot be created or destroyed in a chemical reaction.
  C) Compounds cannot be created or destroyed in a chemical reaction.
  D) Heat cannot be created or destroyed in a chemical reaction.
  Ans:  A     Difficulty:  Easy

 

2. The Greek letter delta (D) may be written over the reaction arrow in a chemical equation to indicate that
  A) Heat is generated when the reaction occurs.
  B) A catalyst is needed for the reaction to occur.
  C) Water is needed for the reaction to occur.
  D) Heat is needed for the reaction to occur.
  Ans:  D     Difficulty:  Easy

 

3. Which chemical equation is properly balanced?
  A) SO2 + O2 + H2O ® H2SO4 C) 4 SO2 + O2 + 4 H2O ® 4 H2SO4
  B) 2 SO2 + O2 + 2 H2O ® 2 H2SO4 D) SO2 + O2 + 4 H2O ® 2 H2SO4
  Ans:  B     Difficulty:  Easy

 

4. In the chemical equation 2 Co(NO3)3 + 3 (NH4)2S ® Co2S3 + 6 NH4NO3 , how many nitrogen atoms are on each side of the equation?
  A)  2    B)  3    C)  6    D)  12    E)  16
  Ans:  D     Difficulty:  Medium

 

5. Write a balanced chemical equation for the reaction of acetone (C3H6O) with oxygen (O2) to form carbon dioxide (CO2) and water (H2O).
  A) C3H6O + O2 ® CO2 + H2O C) 6 C3H6O + 8 O2 ® 6 CO2 + 6 H2O
  B) C3H6O + 4 O2 ® 3 CO2 + 3 H2O D) 3 CO2 + 3 H2O ® C3H6O + 4 O2
  Ans:  B     Difficulty:  Medium

 

6. How many carbon atoms are in 3.85 mol of carbon?
  A) 3.85 carbon atoms D) 2.32 × 1024 carbon atoms
  B) 23.2 carbon atoms E) 6.40 × 10–24 carbon atoms
  C) 6.02 × 1023 carbon atoms    
  Ans:  D     Difficulty:  Easy

 

7. How many iron atoms are in 0.32 mol of Fe2O3?
  A) 3.9 × 1023 iron atoms D) 1.1 × 10–24 iron atoms
  B) 1.9 × 1023 iron atoms E) 6.02 × 1023 iron atoms
  C) 3.9 iron atoms    
  Ans:  A     Difficulty:  Medium

 

8. How many moles of chloroethylene (C2H3Cl) contain 5.47 × 1026 molecules?
  A) 3.29 × 1050 mol of C2H3Cl C) 909 mol of C2H3Cl
  B) 5.47 × 1026 mol of C2H3Cl D) 5450 mol of C2H3Cl
  Ans:  C     Difficulty:  Medium

 

9. What is the formula weight of KCl?
  A)  74.55 amu    B)  66.42 amu    C)  36.00 amu    D)  1386 amu
  Ans:  A     Difficulty:  Easy

 

10. What is the formula weight of Co(NO3)3?
  A)  88.94 amu    B)  244.96 amu    C)  216.94 amu    D)  148.96 amu
  Ans:  B     Difficulty:  Medium

 

11. What is the mass of 3.81 mol of PH3?
  A)  34.0 g    B)  3.81 g    C)  8.92 g    D)  130. g
  Ans:  D     Difficulty:  Medium

 

12. How many moles of carbon dioxide are in 211 g of carbon dioxide?
  A) 929 mol of CO2 C) 167 mol of CO2
  B) 4.79 mol of CO2 D) 0.209 mol of CO2
  Ans:  B     Difficulty:  Medium

 

13. Aspartic acid is an amino acid used to synthesize proteins.  What is the molar mass of aspartic acid shown below?

 

 

  A)  121.09 g/mol    B)  133.11 g/mol    C)  132.09 g/mol    D)  117.0 g/mol
  Ans:  B     Difficulty:  Easy

 

14. Which sample contains the largest number of molecules?
  A)  100 g of CO2    B)  100 g of CH4    C)  100 g of CBr4    D)  100 g of CHBr3
  Ans:  B     Difficulty:  Difficult

 

15. How many moles of sulfur trioxide are formed from 3 moles of sulfur dioxide using the given balanced equation?

 

2 SO2 + O2 ® 2 SO3

  A) 1 mol of SO3 D) 5 mol of SO3
  B) 2 mol of SO3 E) 6 mol of SO3
  C) 3 mol of SO3    
  Ans:  C     Difficulty:  Easy

 

16. How many moles of sulfur trioxide are formed from 3 moles of oxygen using the given balanced equation?

 

2 SO2 + O2 ® 2 SO3

  A) 1 mol of SO3 D) 5 mol of SO3
  B) 2 mol of SO3 E) 6 mol of SO3
  C) 3 mol of SO3    
  Ans:  E     Difficulty:  Medium

 

17. Consider the reaction: 2 Al(OH)3 + 3 H2SO4 ® Al2(SO4)3 + 6 H2O.  How many grams of Al2(SO4)3 are generated when 152 g of H2SO4 reacts?
  A) 530. g of Al2(SO4)3 D) 43.6 g of Al2(SO4)3
  B) 1590 g of Al2(SO4)3 E) 131 g of Al2(SO4)3
  C) 177 g of Al2(SO4)3    
  Ans:  C     Difficulty:  Difficult

 

18. A balanced chemical equation tells the number of _____ of each reactant that combine and the number of _____ of each product formed.
  A)  Grams, grams    B)  Grams, moles    C)  Moles, grams    D)  Moles, moles
  Ans:  D     Difficulty:  Easy

 

19. Suppose the theoretical yield in a reaction is 10.5 g and the percent yield is 75.5%. What is the actual yield of product obtained?
  A)  793 g    B)  7.93 g    C)  13.9 g    D)  0.139 g
  Ans:  B     Difficulty:  Medium

 

20. Consider the oxidation of sodium metal to sodium oxide described by the balanced equation:

 

4 Na + O2 ® 2 Na2O.

What is the theoretical yield of Na2O in grams from 9.0 mol of O2?

  A) 11 g of Na2O D) 280 g of Na2O
  B) 410 g of Na2O E) 560 g of Na2O
  C) 1,100 g of Na2O    
  Ans:  C     Difficulty:  Difficult

 

21. Consider the oxidation of sodium metal to sodium oxide described by the balanced equation:

 

4 Na + O2 ® 2 Na2O.

If 2.55 mol of sodium reacts, and 75.0 g of Na2O is produced, what is the percent yield?

  A)  94.9% yield    B)  34.0% yield    C)  47.5% yield    D)  190.% yield
  Ans:  A     Difficulty:  Difficult

 

22. If a synthesis has four steps and each step has a 75% yield (0.75 written as a decimal), what is the overall percent yield?
  A)  75%    B)  19%    C)  56%    D)  32%    E)  42%
  Ans:  D     Difficulty:  Medium

 

23. Potassium metal (K) reacts violently when added to water according to the balanced equation:

 

2 K(s) + 2 H2O(l) ® 2 KOH(aq) + H2(g).

How many moles of H2O are needed to react completely with 7.54 mol of K?

  A) 2 mol of H2O C) 15.1 mol of H2O
  B) 7.54 mol of H2O D) 3.77 mol of H2O
  Ans:  B     Difficulty:  Medium

 

24. Tin (II) fluoride can be made by the following reaction:  Sn(s) + 2 HF(g) ® SnF2(s) + H2(g).  What is the maximum amount of SnF2 that can be produced when 0.480 moles of Sn are mixed with 0.720 moles of HF?
  A) 0.360 moles of SnF2 D) 0.720 moles of SnF2
  B) 0.480 moles of SnF2 E) 1.20 moles of SnF2
  C) 0.600 moles of SnF2    
  Ans:  A     Difficulty:  Difficult

 

25. Identify the species that is oxidized and the species that is reduced in the reaction:

 

2 I + Cl2 ® 2 Cl + I2

  A) I is oxidized and Cl2 is reduced. D) I2 is oxidized and Cl is reduced.
  B) Cl2 is oxidized and Iis reduced. E) Cl2 is oxidized and Cl is reduced.
  C) I2 is oxidized and I is reduced.    
  Ans:  A     Difficulty:  Medium

 

26. What are the two half reactions that show how many electrons are gained or lost by each species in the reaction:

 

Ni2+(aq) + Mg(s) ® Ni(s) + Mg2+(aq)?

  A) Ni2+(aq) + e ® Ni(s) and Mg(s) ® Mg2+(aq) + e
  B) Ni2+(aq) + 2 e ® Ni(s) and Mg(s) ® Mg2+(aq) + 2 e
  C) Ni2+(aq) ® Ni(s) + 2 e  and Mg(s) + 2 e® Mg2+(aq)
  D) Ni2+(aq) ® Ni(s) + e  and Mg(s) + e® Mg2+(aq)
  E) Ni2+(aq) + 2 e ® Ni(s) and Mg(s) + 2 e ® Mg2+(aq)
  Ans:  B     Difficulty:  Medium

 

27. Which quantity has the greatest mass?
  A) 2.0 mol of Na
  B) 2.0 mol of Na2O
  C) 2.0 mol of NaCl
  D) 2.0 mol of O2
  E) All of these quantities have the same mass.
  Ans:  B     Difficulty:  Medium

 

28. How many moles of sodium chloride (table salt, NaCl, molar mass 58.44 g/mol) are contained in a 1.00 lb box of table salt?
  A) 26,500 mol of NaCl D) 7.77 mol of NaCl
  B) 4.68 × 1024 mol of NaCl E) 0.129 mol of NaCl
  C) 58.44 mol NaCl    
  Ans:  D     Difficulty:  Medium

 

29. In the balanced redox reaction: 2 Cu(s) + S(s) ® Cu2S(s), how many electrons are gained or lost by each copper atom?
  A) Each copper atom gains two (2) electrons
  B) Each copper atom gains one (1) electron
  C) Each copper atom loses one (1) electron
  D) Each copper atom loses two (2) electrons
  Ans:  C     Difficulty:  Difficult

 

30. Consider the mixture of Cl2 and F2 in a closed container as illustrated below.  What will the contents of the container look like if the molecules undergo the reaction:

 

Cl2(g) + 3 F2(g) ® 2 ClF3(g)?

 

 

  A) C)
  B) D)
  Ans:  B     Difficulty:  Difficult

 

31. In the balanced redox reaction: 2 C2H6(g) + 7 O2(g) ® 4 CO2(g) + 6 H2O(g), which species is oxidized?
  A)  C2H6(g)    B)  O2(g)    C)  CO2(g)    D)  H2O(g)
  Ans:  A     Difficulty:  Medium

 

32. In the balanced redox reaction: 2 C2H6(g) + 7 O2(g) ® 4 CO2(g) + 6 H2O(g), which species is reduced?
  A)  C2H6(g)    B)  O2(g)    C)  CO2(g)    D)  H2O(g)
  Ans:  B     Difficulty:  Medium

 

33. How many grams of oxygen gas are required to completely react with 77.28 g of ethane (C2H6) in the balanced redox reaction: 2 C2H6(g) + 7 O2(g) ® 4 CO2(g) + 6 H2O(g)?
  A) 77.28 g of O2(g) D) 143.9 g of O2(g)
  B) 8.995 g of O2(g) E) 287.8 g of O2(g)
  C) 23.50 g of O2(g)    
  Ans:  E     Difficulty:  Difficult

 

34. How many carbon atoms are in 77.28 g of ethane (C2H6)?
  A) 2.570 carbon atoms D) 1.238 × 1025 carbon atoms
  B) 1.548 × 1024 carbon atoms E) 3.094 × 1024 carbon atoms
  C) 5.140 carbon atoms    
  Ans:  E     Difficulty:  Difficult

 

35. What is the molar mass of the compound show below?

 

 

  A) 90.13 amu D) 91.14 g/mol
  B) 93.13 g/mol E) 93.13 amu
  C) 90.13 g/mol    
  Ans:  D     Difficulty:  Easy

 

36. What is the mass of 3.4 × 1020 molecules of ethanol (C2H6O) expressed in milligrams?
  A) 0.026 mg of ethanol C) 26,000 mg of ethanol
  B) 0.012 mg of ethanol D) 26 mg of ethanol
  Ans:  D     Difficulty:  Difficult

 

37. The chemical equation:  KClO3(s)  ®  KCl(s)  +  O2(g) is not balanced.  Balance this equation, then select the statement that best describes the balanced equation.
  A) The balanced equation will have six atoms of oxygen on each side of the equation.
  B) The balanced equation will have one atom of chlorine on each side of the equation.
  C) The balanced equation will have an O3 on the product side of the equation.
  D) The balanced equation will have a coefficient of 1 in front of KCl.
  Ans:  A     Difficulty:  Easy

 

38. Sodium fluoride can be produced from the reaction between sodium metal and fluorine gas.  Which of the following represents the balanced chemical equation for this reaction?
  A) 2 Na(s) + F2(g) ®  2 NaF(s) C) Na+(s) + F(g) ®  NaF(s)
  B) Na(s) + F2(g) ®  NaF2(s) D) 2 Na(s) + F2(g) ®  Na2F2(s)
  Ans:  A     Difficulty:  Medium

 

39. The conversion factor shown below was obtained from the balanced chemical equation: 4 KO2(s) + 2 CO2(g) ® 2 K2CO3(s) + 3 O2(g).  This conversion factor would be used to calculate which of the following?

 

 

  A) The amount of KO2 required to react with a certain amount of O2
  B) The amount of O2 that can react with a certain amount of KO2
  C) The amount of O2 that can be produced from a certain amount of KO2
  D) The amount of KO2 that is required to produce a certain amount of O2
  Ans:  D     Difficulty:  Medium

 

40. Blimps are essentially very large helium filled balloons.  If a blimp contains 536 kg of helium, how many helium atoms are present inside the blimp?
  A) 134,000 He atoms C) 8.9 x 10-19 He atoms
  B) 8.06 x 1028 He atoms D) 3.23 x 1026 He atoms
  Ans:  B     Difficulty:  Difficult

 

41. Beaker A contains 1 mole of iron atoms, and Beaker B contains 1 mole of lead atoms.  Which statement concerning these two samples is known with certainty?

 

 

  A) Beakers A and B contain samples with the same molar mass.
  B) Beakers A and B contain an equal number of atoms.
  C) Beakers A and B contain an equal volume of atoms.
  D) Beakers A and B contain equal masses of atoms.
  Ans:  B     Difficulty:  Medium

 

42. A student runs the reaction: LiOH + CO2 ® LiHCO3.  The reaction consumes 45.0 g LiOH and produces 72.8 g of LiHCO3.  Which of the statements concerning this reaction is true?
  A) The actual yield of the product is 72.8 g LiHCO3.
  B) The theoretical yield of the product is 72.8 g LiHCO3.
  C) The theoretical yield of the product is 117.8 g LiHCO3.
  D) The percent yield of the reaction is 61.8%.
  Ans:  A     Difficulty:  Easy

 

43. Assume that the mixture of substances in Figure 1 undergoes a chemical reaction.  Which diagram represents a product mixture that is consistent with the Law of Conservation of Mass?

 

 

 

  A)
  B)
  C)
  D) It is impossible to predict based on the information given.
  Ans:  A     Difficulty:  Medium

 

44. The subscripts in chemical formulas are changed in order to balance a chemical equation.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

45. A chemical equation is balanced by adding coefficients in front of some formulas so that the number of atoms of each element is equal on both sides of the equation.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

46. A mole of copper atoms has more atoms than a mole of lead atoms.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

47. One mole of oxygen molecules contains more atoms than one mole of lead atoms.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

48. The molar mass of CaCO3 is greater than the molar mass of Ca(NO3)2.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

49. The actual yield is the amount of product expected from a given amount of reactant based on the coefficients in the balanced chemical equation.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

50. In calculating the percent yield, both the actual yield and theoretical yield must be in units of grams.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

51. Oxidation is the gain of electrons by an atom.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

52. All chemical reactions convert one substance into another.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

53. In the reaction: Ni2+(aq) + Mg(s) ® Ni(s) + Mg2+(aq), the oxidizing agent is Ni2+(aq).
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

54. In the reaction: Ni2+(aq) + Mg(s) ® Ni(s) + Mg2+(aq), the species that undergoes reduction is Mg(s).
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

55. Combustion reactions are redox reactions.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

56. The balanced reaction: 4 NO2 + O2 + 2 H2O ® 4 HNO3 states that four moles of nitrogen dioxide react with each mole of oxygen.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

57. The balanced reaction: 4 NO2 + O2 + 2 H2O ® 4 HNO3 states that four grams of nitrogen dioxide reacts with each gram of oxygen.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

58. The balanced reaction:  4 Fe(s) + 3 O2(g) ® 2 Fe2O3(s) is an oxidation-reduction reaction.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

59. A mole is a quantity that contains 6.02 × 10–23 atoms, molecules, or ions.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

60. The formula weight of a compound is the sum of the atomic weights of all the atoms in a compound, reported in atomic mass units.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

61. When the mass of a substance produced in a reaction must be calculated, first its number of moles is determined using mole ratios, and then Avogadro’s number is used to convert moles to grams.
  A)  True    B)  False
  Ans:  B     Difficulty:  Easy

 

62. The actual yield of a product in a chemical reaction should not exceed its theoretical yield.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

63. In redox reactions, metals tend to undergo oxidation.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

64. The electric current generated in batteries used for portable electronic devices and pacemakers results from redox reactions.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

65. The reaction: Mg(s) + 2 HBr(aq) ® MgBr2(s) + H2(g) is an oxidation-reduction reaction.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

66. Consider the balanced reaction: 4 NO2 + O2 + 2 H2O ® 4 HNO3.  If 100. g of NO2 is placed in a reaction vessel the theoretical yield of nitric acid (HNO3) collected will be 137 g.
  A)  True    B)  False
  Ans:  A     Difficulty:  Difficult

 

67. In a chemical reaction, the actual yield of a product may be reduced by side reactions.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

68. 2 Co(NO3)3(aq) + 3 (NH4)2S(aq) ® Co2S3(s) + 3 NH4NO3(aq) is a properly balanced chemical equation.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

69. To determine the overall percent yield in a synthesis that has more than one step, subtract the percent yield for each step from 100% yield.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

70. Consider the balanced reaction: 2 A + B ® C, where the molar mass of B is less than the molar mass of A.  It requires a smaller mass of A to completely react with given mass of B.
  A)  True    B)  False
  Ans:  B     Difficulty:  Difficult

 

71. In the reaction: Ni2+(aq) + Mg(s) ® Ni(s) + Mg2+(aq), two electrons are transferred from Ni2 to Mg.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

72. A 100-g sample of the compound below contains greater than one mole of molecules.

 

 

  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

73. A 100-g sample of the compound below contains less than 6.02 × 1023 molecules.

 

 

  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

74. One term in a balanced chemical equation contains the coefficient 4 in front of the formula Mg3(PO4)2.  This term represents that there are 12 Mg atoms, 4 P atoms and 16 O atoms in this term.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

75. To multiply two numbers in scientific notation, multiply the coefficients together and multiply the exponents in the powers of 10.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

76. The molar mass of dibromomethane (CH2Br2) is larger than the molar mass of dichloromethane (CH2Cl2).
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

77. A 200.-mg ibuprofen (C13H18O2) tablet contains greater than one mole of ibuprofen molecules.
  A)  True    B)  False
  Ans:  B     Difficulty:  Medium

 

78. Consider the unbalanced chemical equation:  NH3 + O2 ® NO + H2O.   It requires 55.4 g of NH3 to completely react with 156 g of O2.
  A)  True    B)  False
  Ans:  B     Difficulty:  Difficult

 

79. The mass of one ethanol (C2H6O) molecule is 7.65 × 10–23 grams.
  A)  True    B)  False
  Ans:  A     Difficulty:  Medium

 

80. A chemical change alters the chemical composition of a substance, and therefore a new substance is produced.
  A)  True    B)  False
  Ans:  A     Difficulty:  Easy

 

81. A chemical equation is an expression that uses chemical formulas and other symbols to illustrate what _____ constitute the starting materials in a reaction and what _____ are formed.
  Ans: reactants, products
  Difficulty:  Easy

 

82. When calculating the number of moles of calcium hydroxide formed from each mole of sodium hydroxide in the balanced reaction: CaCl2 + 2 NaOH ® Ca(OH)2 + 2 NaCl, the necessary conversion factor is _____.
  Ans:
  Difficulty:  Easy

 

83. A redox reaction involves the transfer of _____ from one element to another.
  Ans: electrons
  Difficulty:  Easy

 

84. A compound that gains electrons in a redox reaction while causing another compound to be oxidized is called a(n) _____ agent.
  Ans: oxidizing
  Difficulty:  Medium

 

85. _____ results in the loss of oxygen atoms or the gain of hydrogen atoms.
  Ans: Reduction
  Difficulty:  Medium

 

86. In a redox reaction, the _____ agent is the substance that gets oxidized.
  Ans: reducing
  Difficulty:  Medium

 

87. In a two-step synthesis where the first reaction has a 55% yield and the second reaction has a 24% yield, the overall percent yield of the reaction is _____% yield.
  Ans: 13
  Difficulty:  Medium

 

88. In the balanced reaction:  2 I + Cl2 ® 2 Cl + I2, _____ is the reducing agent and _____ is the oxidizing agent.
  Ans: I, Cl2
  Difficulty:  Medium

 

89. Aluminum metal and oxygen gas are obtained when aluminum oxide is heated at high temperature.  The reactant(s) in this chemical reaction is(are) _____.
  Ans: aluminum oxide
  Difficulty:  Easy

 

90. The combustion of hexane (C6H14), a component of gasoline, is represented by the balanced chemical equation: 2 C6H14(l) + 19 O2(g) ® 12 CO2(g) + 14 H2O(g).  If 1.0 mole of hexane undergoes combustion, _____ moles of O2 are required.
  Ans: 9.5
  Difficulty:  Medium

 

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