Exam

Name___________________________________

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

1) A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be __________. 1)A) N2O4B) NO2C) N2OD) NOE) either NO2 or N2O4

2) What is the mass in grams of 9.76 × 1012 atoms of naturally occurring sodium? 2)A) 22.99B) 7.05 × 10-13

C) 3.73 × 10-10

D) 1.62 × 10-11

E) 2.24 × 1014

3) A sulfur oxide is 50.0% by mass sulfur. This molecular formula could be __________. 3)A) SO2B) S2O4C) S2OD) SOE) either SO2 or S2O4

4) The reaction used to inflate automobile airbags __________. 4)A) produces sodium gasB) is a combination reactionC) is a decomposition reactionD) is a combustion reactionE) violates the law of conservation of mass

5) The formula weight of ammonium sulfate ((NH4)2SO4), rounded to the nearest integer, is__________ amu.

5)

A) 132 B) 100 C) 264 D) 118 E) 116

6) Lithium and nitrogen react to produce lithium nitride:

6Li (s) + N2 (g) 2Li3N (s)

How many moles of lithium nitride are produced when 0.450 mol of lithium react in this fashion?

6)

A) 1.35 B) 0.225 C) 0.900 D) 0.150 E) 0.0750

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7) Which one of the following substances is the product of this combination reaction?

Al (s) + I2 (s) __________

7)

A) AlI2 B) Al3I2 C) Al2I3 D) AlI E) AlI3

8) How many atoms of nitrogen are in 10 g of NH4NO3? 8)

A) 1.5 × 1023 B) 2 C) 1.8 D) 3.0 × 1023 E) 3.5

9) The total number of atoms in 0.111 mol of Fe(CO)3(PH3)2 is __________. 9)A) 1.67B) 15.0C) 2.76 × 10-24

D) 1.00 × 1024

E) 4.46 × 1021

10) The mass % of Al in aluminum sulfate (Al2(SO4)3) is __________. 10)A) 15.77 B) 45.70 C) 7.886 D) 35.94 E) 21.93

11) When the following equation is balanced, the coefficients are __________.

C8H18 + O2 CO2 + H2O

11)

A) 2, 3, 4, 4B) 2, 25, 16, 18C) 2, 12, 8, 9D) 4, 4, 32, 36E) 1, 4, 8, 9

12) Calculate the percentage by mass of lead in Pb(NO3)2. 12)A) 44.5 B) 62.6 C) 65.3 D) 38.6 E) 71.2

13) A 30.5 gram sample of glucose (C6H12O6) contains __________ atoms of carbon. 13)

A) 1.22 x 1024

B) 6.02 x 1023

C) 6.12 x 1023

D) 2.04 x 1023

E) 1.02 x 1023

14) The formula weight of lead nitrate (Pb(NO3)2) is __________ amu. 14)A) 285.2 B) 269.2 C) 317.2 D) 538.4 E) 331.2

15) A 30.5 gram sample of glucose (C6H12O6) contains __________ mol of glucose. 15)A) 5.90 B) 0.136 C) 0.169 D) 0.424 E) 2.36

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16) Gaseous argon has a density of 1.40 g/L at standard conditions. How many argon atoms are in 1.00L of argon gas at standard conditions?

16)

A) 1.59 × 1025

B) 6.02 × 1023

C) 4.76 × 1022

D) 2.11 × 1022

E) 3.43 × 1025

17) How many sulfur dioxide molecules are there in 1.80 mol of sulfur dioxide? 17)A) 1.80 × 1024

B) 1.08 × 1024

C) 6.02 × 1023

D) 6.02 × 1024

E) 1.08 × 1023

18) The formula weight of calcium nitrate (Ca(NO3)2), rounded to one decimal place, is __________amu.

18)

A) 102.1 B) 116.1 C) 150.1 D) 164.0 E) 204.2

19) A sample of CH2F2 with a mass of 19 g contains __________ atoms of F. 19)

A) 2.2 × 1023 B) 38 C) 4.4 × 1023 D) 9.5 E) 3.3 × 1024

20) Calculate the percentage by mass of oxygen in Pb(NO3)2. 20)A) 14.5 B) 19.3 C) 29.0 D) 33.4 E) 9.7

21) How many oxygen atoms are contained in 2.74 g of Al2(SO4)3? 21)A) 12B) 8.01 × 10-3

C) 5.79 × 1022

D) 6.02 × 1023

E) 7.22 × 1024

22) The mass % of C in methane (CH4) is __________. 22)A) 7.743 B) 133.6 C) 92.26 D) 25.13 E) 74.87

23) Which one of the following is not true concerning automotive air bags? 23)A) The two products of the decomposition reaction are sodium and nitrogenB) They are inflated as a result of a decomposition reactionC) A gas is produced when the air bag activates.D) They are loaded with sodium azide initiallyE) The gas used for inflating them is oxygen

24) The formula weight of silver chromate (Ag2CrO4) is __________ amu. 24)A) 331.73 B) 159.87 C) 175.87 D) 223.87 E) 339.86

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25) Calcium oxide reacts with water in a combination reaction to produce calcium hydroxide:

CaO (s) + H2O (l) Ca(OH)2 (s)

A 4.50-g sample of CaO is reacted with 4.34 g of H2O. How many grams of water remains aftercompletion of reaction?

25)

A) 1.04 B) 0.00 C) 0.161 D) 0.00892 E) 2.90

26) What is the empirical formula of a compound that is 62.0% C, 10.4% H, and 27.5% O by mass? 26)A) C5H10O2B) C6HO3C) C3H6OD) C3HOE) C6H12O2

27) Which of the following are combustion reactions?1) CH4 (g) + O2 (g) CO2 (g) + H2O (l)2) CaO (s) + CO2 (g) CaCO3 (s)3) PbCO3 (s) PbO (s) + CO2 (g)4) CH3OH (l) + O2 (g) CO2 (g) + H2O (l)

27)

A) 1, 3, and 4B) 3 and 4C) 1, 2, 3, and 4D) 1 and 4E) 2, 3, and 4

28) Sulfur and oxygen react to produce sulfur trioxide. In a particular experiment, 7.9 grams of SO3 areproduced by the reaction of 5.0 grams of O2 with 6.0 grams of S. What is the % yield of SO3 in thisexperiment?

S (s) + O2 (g) SO3 (g) (not balanced)

28)

A) 63 B) 95 C) 99 D) 32 E) 75

29) The molecular weight of urea ( (NH2)2CO ), a compound used as a nitrogen fertilizer, is__________ amu (rounded to one decimal place).

29)

A) 44.0 B) 43.0 C) 8.0 D) 32.0 E) 60.1

30) How many oxygen atoms are there in 52.06 g of carbon dioxide? 30)A) 1.204 × 1024

B) 1.018 × 1024

C) 6.022 × 1023

D) 5.088 × 1023

E) 1.424 × 1024

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31) Which of the following are decomposition reactions?1) CH4 (g) + O2 (g) CO2 (g) + H2O (l)2) CaO (s) + CO2 (g) CaCO3 (s)3) Mg (s) + O2 (g) MgO (s)4) PbCO3 (s) PbO (s) + CO2 (g)

31)

A) 4 onlyB) 1, 2, and 3C) 1, 2, 3, and 4D) 2 and 3E) 2, 3, and 4

32) Lithium and nitrogen react to produce lithium nitride:

6Li (s) + N2 (g) 2Li3N (s)

How many moles of N2 are needed to react with 0.500 mol of lithium?

32)

A) 0.500 B) 3.00 C) 0.0833 D) 1.50 E) 0.167

33) How many moles of sodium carbonate contain 1.773 × 1017 carbon atoms? 33)A) 5.890 × 10-7

B) 1.473 × 10-7

C) 2.945 × 10-7

D) 9.817 × 10-8

E) 8.836 × 10-7

34) The formula weight of potassium dichromate (K2Cr2O7) is __________ amu. 34)A) 107.09 B) 294.18 C) 255.08 D) 333.08 E) 242.18

35) Calcium oxide reacts with water in a combination reaction to produce calcium hydroxide:

CaO (s) + H2O (l) Ca(OH)2 (s)

In a particular experiment, a 5.00-g sample of CaO is reacted with excess water and 6.11 g ofCa(OH)2 is recovered. What is the percent yield in this experiment?

35)

A) 7.19 B) 92.5 C) 81.9 D) 122 E) 1.22

36) How many sulfur dioxide molecules are there in 0.180 mol of sulfur dioxide? 36)A) 1.08 × 1023

B) 1.80 × 1023

C) 6.02 × 1023

D) 1.08 × 1024

E) 6.02 × 1024

37) The molecular formula of aspartame, the generic name of NutraSweet®, is C14H18N2O5. Themolar mass of aspartame, rounded to the nearest integer, is __________ g.

37)

A) 156 B) 24 C) 294 D) 43 E) 39

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38) How many molecules of CH4 are in 48.2 g of this compound? 38)A) 4.00B) 3.00C) 2.90 × 1025

D) 1.81 × 1024

E) 5.00 × 1024

39) Propane (C3H8) reacts with oxygen in the air to produce carbon dioxide and water. In a particularexperiment, 38.0 grams of carbon dioxide are produced from the reaction of 22.05 grams ofpropane with excess oxygen. What is the % yield in this reaction?

39)

A) 94.5 B) 38.0 C) 86.4 D) 66.0 E) 57.6

40) The mass % of F in the binary compound KrF2 is __________. 40)A) 68.80 B) 45.38 C) 18.48 D) 31.20 E) 81.52

41) Magnesium burns in air with a dazzling brilliance to produce magnesium oxide:

2Mg (s) + O2 (g) 2MgO (s)

When 4.00 g of magnesium burns, the theoretical yield of magnesium oxide is __________ g.

41)

A) 3.32 B) 4.00 C) 6.63 D) 0.165 E) 13.3

42) Lithium and nitrogen react in a combination reaction to produce lithium nitride:

6Li (s) + N2 (g) 2Li3N (s)

How many moles of lithium are needed to produce 0.60 mol of Li3N when the reaction is carriedout in the presence of excess nitrogen?

42)

A) 0.40 B) 1.8 C) 0.30 D) 0.20 E) 3.6

43) The molecular weight of the acetic acid (CH3CO2H), rounded to the nearest integer, is __________amu.

43)

A) 32 B) 60 C) 44 D) 48

44) There are ________ oxygen atoms in 30 molecules of C20H42S3O2 44)

A) 1.2 x 1024 B) 1.8 x 1025 C) 60 D) 3.6 x 1025 E) 6.0 x 1023

45) The formula weight of magnesium fluoride (MgF2), rounded to one decimal place, is __________amu.

45)

A) 62.3 B) 92.9 C) 43.3 D) 67.6 E) 86.6

46) The molecular weight of glucose (C6H12O6), rounded to the nearest integer, is __________ amu. 46)A) 180 B) 224 C) 24 D) 96 E) 136

47) The formula of nitrobenzene is C6H5NO2. The molecular weight of this compound is __________amu.

47)

A) 107.11 B) 123.11 C) 43.03 D) 109.10 E) 3.06

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48) Calculate the percentage by mass of hydrogen in PtCl2(NH3)2. 48)A) 2.016 B) 1.008 C) 1.558 D) 0.034 E) 0.672

49) The compound responsible for the characteristic smell of garlic is allicin, C6H10OS2. The mass of1.00 mol of allicin, rounded to the nearest integer, is __________ g.

49)

A) 162 B) 19 C) 86 D) 61 E) 34

50) One million argon atoms is __________ mol (rounded to two significant figures) of argon atoms. 50)A) 3.0B) 1.7 × 10-18

C) 1.0 × 10+6

D) 6.0 × 1023

E) 1.0 × 10-6

51) Of the reactions below, which one is a decomposition reaction? 51)A) 2N2 + 3H2 2NH3B) NH4Cl NH3 + HClC) Cd(NO3)2 + Na2S CdS + 2NaNO3D) 2CH4 + 4O2 2CO2 + 4H2OE) 2Mg + O2 2MgO

52) Which of the following are combination reactions?1) CH4 (g) + O2 (g) CO2 (g) + H2O (l)2) CaO (s) + CO2 (g) CaCO3 (s)3) Mg (s) + O2 (g) MgO (s)4) PbCO3 (s) PbO (s) + CO2 (g)

52)

A) 1, 2, and 3B) 2, 3, and 4C) 1, 2, 3, and 4D) 4 onlyE) 2 and 3

53) One mole of __________ contains the largest number of atoms. 53)A) S8 B) Cl2 C) C10H8 D) Al2(SO4)3 E) Na3PO4

54) Automotive air bags inflate when sodium azide decomposes explosively to its constituent elements:

2NaN3 (s) 2Na (s) + 3N2 (g)

How many grams of sodium azide are required to produce 33.0 g of nitrogen?

54)

A) 76.6 B) 114.9 C) 51.1 D) 0.785 E) 1.77

55) How many moles of pyridine (C5H5N) are contained in 3.13 g of pyridine? 55)

A) 0.00404 B) 25.3 C) 0.0396 D) 4.04 × 103 E) 0.319

56) The molecular weight of the ethanol (C2H5OH), rounded to the nearest integer, is __________ amu. 56)A) 41 B) 46 C) 30 D) 34 E) 92

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57) The formula weight of potassium phosphate (K3PO4) is __________ amu. 57)A) 212.27 B) 196.27 C) 251.37 D) 86.07 E) 173.17

58) When a hydrocarbon burns in air, what component of air reacts? 58)A) waterB) oxygenC) carbon dioxideD) argonE) nitrogen

59) The formula weight of aluminum sulfate (Al2(SO4)3) is __________ amu. 59)A) 150.14 B) 59.04 C) 123.04 D) 342.15 E) 273.06

60) What is the mass % of carbon in dimethylsulfoxide (C2H6SO) rounded to three significant figures? 60)A) 20.6 B) 79.8 C) 7.74 D) 60.0 E) 30.7

61) Calculate the percentage by mass of nitrogen in PtCl2(NH3)2. 61)A) 12.67 B) 4.67 C) 9.34 D) 4.95 E) 9.90

62) The mass % of H in methane (CH4) is __________. 62)A) 92.26 B) 4.032 C) 7.743 D) 25.13 E) 74.87

63) There are __________ atoms of oxygen are in 300 molecules of CH3CO2H. 63)A) 600B) 1.80 × 1026

C) 3.01 × 1024

D) 3.61 × 1026E) 300

64) Calculate the percentage by mass of nitrogen in Pb(NO3)2. 64)A) 5.2 B) 8.5 C) 4.2 D) 12.6 E) 10.4

65) Magnesium burns in air with a dazzling brilliance to produce magnesium oxide:

2Mg (s) + O2 (g) 2MgO (s)

How many moles of O2 are consumed when 0.770 mol of magnesium burns?

65)

A) 2.60 B) 0.385 C) 0.770 D) 0.0317 E) 1.54

66) The formula weight of a substance is __________. 66)A) identical to the molar massB) the same as the percent by mass weightC) the weight of a sample of the substanceD) the sum of the atomic weights of each atom in its chemical formulaE) determined by combustion analysis

67) Calculate the percentage by mass of chlorine in PtCl2(NH3)2. 67)A) 25.05 B) 12.53 C) 11.82 D) 18.09 E) 23.63

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68) How many grams of sodium carbonate contain 1.773 × 1017 carbon atoms? 68)A) 6.066 × 10-5

B) 1.011 × 10-5

C) 3.121 × 10-5

D) 1.517 × 10-5

E) 9.100 × 10-5

69) Lithium and nitrogen react in a combination reaction to produce lithium nitride:

6Li (s) + N2 (g) 2Li3N (s)

In a particular experiment, 3.50-g samples of each reagent are reacted. The theoretical yield oflithium nitride is __________ g.

69)

A) 2.93 B) 3.52 C) 17.6 D) 8.7 E) 5.85

70) A sample of CH4O with a mass of 32.0 g contains __________ molecules of CH4O. 70)A) 1.00B) 5.32 × 10-23

C) 1.88 × 1022D) 32.0E) 6.02 × 1023

71) Which hydrocarbon pair below have identical mass percentage of C? 71)A) C2H4 and C4H2B) C3H4 and C3H6C) C2H4 and C3H4D) C2H4 and C3H6E) none of the above

72) How many carbon atoms are there in 52.06 g of carbon dioxide? 72)A) 3.134 × 1025

B) 7.122 × 1023

C) 1.424 × 1024

D) 5.206 × 1024

E) 8.648 × 10-23

73) Of the reactions below, which one is not a combination reaction? 73)A) 2Mg + O2 2MgOB) 2N2 + 3H2 2NH3C) CaO + H2O Ca(OH)2D) C + O2 CO2E) 2CH4 + 4O2 2CO2 + 4H2O

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74) Automotive air bags inflate when sodium azide decomposes explosively to its constituent elements:

2NaN3 (s) 2Na (s) + 3N2 (g)

How many moles of N2 are produced by the decomposition of 2.88 mol of sodium azide?

74)

A) 4.32 B) 1.44 C) 0.960 D) 8.64 E) 1.92

75) When the following equation is balanced, the coefficient of H2O is __________.

Ca (s) + H2O (l) Ca(OH)2 (aq) + H2 (g)

75)

A) 2 B) 3 C) 4 D) 5 E) 1

76) A compound contains 40.0% C, 6.71% H, and 53.29% O by mass. The molecular weight of thecompound is 60.05 amu. The molecular formula of this compound is __________.

76)

A) CHO2 B) C2H4O2 C) C2H3O4 D) C2H2O4 E) CH2O

77) When the following equation is balanced, the coefficient of water is __________.

K (s) + H2O (l) KOH (aq) + H2 (g)

77)

A) 5 B) 3 C) 4 D) 2 E) 1

78) When the following equation is balanced, the coefficient of O2 is __________.

C2H4O (g) + O2 (g) CO2 (g) + H2O (g)

78)

A) 2 B) 5 C) 3 D) 1 E) 4

79) The combustion of ammonia in the presence of excess oxygen yields NO2 and H2O:

4 NH3 (g) + 7 O2 (g) 4 NO2 (g) + 6 H2O (g)

The combustion of 28.8 g of ammonia consumes __________ g of oxygen.

79)

A) 28.8 B) 94.7 C) 54.1 D) 108 E) 15.3

80) What is the maximum mass in grams of NH3 that can be produced by the reaction of 1.0 g of N2with 3.0 g of H2 via the equation below?

N2 (g) + H2 (g) NH3 (g) (not balanced)

80)

A) 17 B) 0.61 C) 1.2 D) 4.0 E) 2.0

81) GeF3H is formed from GeH4 and GeF4 in the combination reaction:

GeH4 + 3GeF4 4GeF3H

If the reaction yield is 92.6%, how many moles of GeF4 are needed to produce 8.00 mol of GeF3H?

81)

A) 6.48 B) 5.56 C) 2.16 D) 2.78 E) 3.24

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82) How many moles of magnesium oxide are produced by the reaction of 3.82 g of magnesium nitridewith 7.73 g of water?

Mg3N2 + 3H2O 2NH3 + 3MgO

82)

A) 4.57 B) 0.0378 C) 0.0756 D) 0.114 E) 0.429

83) Write the balanced equation for the reaction that occurs when methanol, CH3OH (l), is burned inair. What is the coefficient of methanol in the balanced equation?

83)

A) 1 B) 2 C) 3 D) 4 E) 3/2

84) Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride:

S (s) + 3F2 (g) SF6 (g)

In a particular experiment, the percent yield is 79.0%. This means that in this experiment, a 7.90-gsample of fluorine yields __________ g of SF6.

84)

A) 10.1 B) 7.99 C) 24.0 D) 30.3 E) 0.110

85) A compound contains 38.7% K, 13.9% N, and 47.4% O by mass. What is the empirical formula ofthe compound?

85)

A) KNO3 B) KNO2 C) K2N2O3 D) K4NO5 E) K2NO3

86) When the following equation is balanced, the coefficients are __________.

NH3 (g) + O2 (g) NO2 (g) + H2O (g)

86)

A) 4, 3, 4, 3 B) 1, 1, 1, 1 C) 2, 3, 2, 3 D) 1, 3, 1, 2 E) 4, 7, 4, 6

87) A sample of C3H8O that contains 200 molecules contains __________ carbon atoms. 87)A) 600B) 200C) 3.61 × 1026

D) 4.01 × 1025

E) 1.20 × 1026

88) A compound that is composed of only carbon and hydrogen contains 85.7% C and 14.3% H bymass. What is the empirical formula of the compound?

88)

A) C2H4 B) CH4 C) C4H8 D) C86H14 E) CH2

89) Magnesium and nitrogen react in a combination reaction to produce magnesium nitride:

3 Mg + N2 Mg3N2

In a particular experiment, a 9.27-g sample of N2 reacts completely. The mass of Mg consumed is__________ g.

89)

A) 0.92 B) 13.9 C) 24.1 D) 16.1 E) 8.04

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90) Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yieldammonia:

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

A 7.1-g sample of N2 requires __________ g of H2 for complete reaction.

90)

A) 17.2 B) 0.76 C) 1.5 D) 1.2 E) 0.51

91) The combustion of propane (C3H8) in the presence of excess oxygen yields CO2 and H2O:

C3H8 (g) + 5O2 (g) 3CO2 (g) + 4H2O (g)

When 2.5 mol of O2 are consumed in their reaction, __________ mol of CO2 are produced.

91)

A) 3.0 B) 2.5 C) 1.5 D) 6.0 E) 5.0

92) Lead (II) carbonate decomposes to give lead (II) oxide and carbon dioxide:

PbCO3 (s) PbO (s) + CO2 (g)

How many grams of lead (II) oxide will be produced by the decomposition of 2.50 g of lead (II)carbonate?

92)

A) 2.61 B) 0.41 C) 2.50 D) 0.00936 E) 2.09

93) When the following equation is balanced, the coefficient of Al is __________.

Al (s) + H2O (l) Al(OH)3 (s) + H2 (g)

93)

A) 2 B) 3 C) 1 D) 4 E) 5

94) Solid aluminum and gaseous oxygen react in a combination reaction to produce aluminum oxide:

4Al (s) + 3O2 (g) 2Al2O3 (s)

The maximum amount of Al2O3 that can be produced from 2.5 g of Al and 2.5 g of O2 is__________ g.

94)

A) 5.3 B) 9.4 C) 5.0 D) 7.4 E) 4.7

95) When the following equation is balanced, the coefficient of water is __________.

N2O5 (g) + H2O (l) HNO3 (aq)

95)

A) 2 B) 3 C) 5 D) 4 E) 1

96) What is the empirical formula of a compound that contains 49.4% K, 20.3% S, and 30.3% O bymass?

96)

A) KSO4 B) KSO3 C) KSO2 D) K2SO3 E) K2SO4

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97) When the following equation is balanced, the coefficient of Al2O3 is __________.

Al2O3 (s) + C (s) + Cl2 (g) AlCl3 (s) + CO (g)

97)

A) 5 B) 2 C) 1 D) 3 E) 4

98) Write the balanced equation for the reaction that occurs when methanol, CH3OH (l), is burned inair. What is the coefficient of oxygen in the balanced equation?

98)

A) 1 B) 2 C) 3 D) 4 E) 3/2

99) How many grams of hydrogen are in 46 g of CH4O? 99)A) 0.36 B) 1.5 C) 5.8 D) 2.8 E) 184

100) When the following equation is balanced, the coefficient of C3H8O3 is __________.

C3H8O3 (g) + O2 (g) CO2 (g) + H2O (g)

100)

A) 7 B) 2 C) 1 D) 5 E) 3

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