CHEMISTRY TEST
CHEMISTRY TEST NAME: _____________________
THE MOLE CONCEPT
DATE: _____________________
Directions: For each of the following questions, choose the
number that best answers the question and place it on your answer sheet.
Directions: For each of the following questions, all major
steps must be shown to receive
full credit.
The Mole Concept
Level 1
Multiple Choice
1. The sample of oxygen at S.T.P. which represents the greatest mass is one
1) mole; 2) gram; 3) molecule; 4) liter.
ANS: 1
2. The mass of a mole of a gas
divided by 22.4 liters equals 1) the
density of the gas
at STP; 2) the volume of the gas; 3) the empirical formula of the
gas;
4) the volume of 6.02 x 1023 molecules of the gas.
ANS: 1
3. The formula for one molecule of hydrogen is
1) H2; 2) 2 H; 3) 2 H+; 4) 2 H-; 5) none of these.
ANS: 1
4. The formula CO2 does
not give information about
1) the elements which make up
the compound.
2) the number of atoms of each
element in the compound.
3) the solubility of the
compound in water.
4) the relative mass of the
molecule.
ANS: 3
5. The molecular formula H2O represents all of the following except 1) one molecule
of water; 2) the relative number of atoms in a
molecule; 3) one formula mass
of water; 4) one gram of water; 5) one mole of water.
ANS: 4
6. The atomic mass of Mg is 24,
and the atomic mass of Cl is 35.5. One
mole of MgCl2
1) represents 95 molecules of the compound. 3) contains 35.5 molecules of chlorine.
2) represents 95 grams of the compound. 4) contains 2 moles of chlorine
molecules.
ANS: 2
7. If two containers of different gases under the same conditions have
the same number
of molecules, the gases must
have 1) an equal number of
atoms; 2) equal
molecular
masses; 3) equal volumes; 4) equal masses.
ANS: 3
8. How many mole(s) of calcium carbonate is represented by 50 grams of
the compound?
1) 1.0 m. 2) 2.0 m. 3) 0.20 m. 4) 4.0 m. 5) 0.50 m.
1) 1.0 m. 2) 2.0 m. 3) 0.20 m. 4) 4.0 m. 5) 0.50 m.
ANS: 5
9. How many moles are there in 120 grams of neon?
1) 2.4 moles 2) 4.2 moles 3) 6.0 moles 4) 10.0 moles
ANS: 3
10. The mass of one mole of ammonium carbonate is approximately
1) 43.0 g; 2) 72.0 g; 3) 78.0 g; 4) 96.0 g; 5) none of these.
ANS: 4
11. What is the mass of 3.4
moles of aluminum hydroxide?
1) 156.4 g. 2) 207.4 g. 3) 265.2 g. 4) 294.1 g.
ANS: 3
12. How many grams are there in 0.85 moles of iodine?
1) 48 g. 2) 108 g. 3) 127 g. 4) none of these
ANS: 4
13. What is the mass of one mole of tin (II) fluoride?
1) 59.0 g. 2) 68.0 g. 3) 138 g. 4) 157 g. 5) 126 g.
ANS: 4
14. A liter of a certain gas weighs 1.25 grams at
S.T.P. The mass of one mole of this
gas is 1) 1.25 g; 2) 22.4 g; 3) between 1.25 and 2.0 g; 4) 28 g; 5) 32 g.
ANS: 4
15. Which sample contains the same number of atoms as 24 grams of carbon?
1) 80 gram Ar 2) 24 gram Mg 3) 10 gram Ne 4) 4.0 gram He
ANS: 1
16. What is the number of moles
present in 862 grams of calcium hydrogen sulfate?
1) 6.3 moles 2) 5.2 moles 3) 3.7 moles 4) 4.1 moles 5) none of these
ANS: 3
17. The mass of 1 mole of CaSO4.2H2O
is 1) 11 g; 2) 154 g; 3) 172 g;
4) 200 g; 5) 217 g.
ANS: 3
18. What is the mass of one
mole of the gasoline additive lead tetraethyl, Pb(C2H5)4?
1) 323 g. 2) 251 g. 3) 236 g. 4) 150 g.
ANS: 1
19. What is the approximate
mass of a mole of carbon tetrachloride, CCl4?
1) 1.00 gram 2) 22.4 grams 3) 47.5 grams 4) 83.5 grams 5) 154 grams
ANS: 5
20. In one gram-molecular mass
of copper (II) sulfate, the total mass of oxygen is
1) 16 grams; 2) 48 grams; 3) 64 grams; 4) 144 grams.
ANS: 3
21. How many moles are there in 75 grams of calcium?
1) 1.9 moles 2) 2.4 moles 3) 4.2 moles 4) 40 moles 5) none of these
ANS: 1
1) 1.9 moles 2) 2.4 moles 3) 4.2 moles 4) 40 moles 5) none of these
ANS: 1
22. How many moles are there in
100 grams of the element helium?
1) 12.5 m. 2) 25.0 m. 3) 50.0 m. 4) 100 m. 5) 400 m.
1) 12.5 m. 2) 25.0 m. 3) 50.0 m. 4) 100 m. 5) 400 m.
ANS: 2
23. What is the mass of 3.4 moles of chromic dichromate?
1) 207.4 g. 2) 394.8 g. 3) 752.0 g. 4) 911.2 g. 5) 2,556.8 g.
ANS: 5
24. How many moles of hydrogen
cyanide, HCN, are contained in 9.00 grams of HCN?
1) 0.090 m. 2) 0.333 m. 3) 1.00 m. 4) 9.00 m.
ANS: 2
25. How many grams are there in 1.5 moles of zinc?
1) 15 grams 2) 47 grams 3) 65 grams 4) 98 grams
ANS: 4
26. Calculate the number of moles in 400 grams of mercuric hydroxide.
1) 1.71 moles 2) 1.84 moles 3) 2.40 moles 4) 3.10 moles
ANS: 1
27. How many moles are there in 600.0 grams of sodium dichromate?
1) 1.6 m. 2) 2.3 m. 3) 3.1 m. 4) 3.7 m. 5) none of these
ANS: 2
28. The number of moles of sodium chloride represented by 117 grams is
1) 1 m; 2) 2 m; 3) 3 m; 4) 3.25 m; 5) 22.4 m.
ANS: 2
29. Calculate the mass of 3.0
moles of ethyl alcohol, C2H5OH.
1) 46
grams 2) 69 grams 3) 82 grams 4) 118 grams 5) 138 grams
ANS: 5
30. What is the mass of two
moles of calcium chloride?
1) 80
grams 2) 151 grams 3) 202 grams 4) 222 grams 5) 231 grams
ANS: 4
31. Calculate the number of moles in 800 grams of aluminum sulfate.
1) 2.3 m. 2) 2.9 m. 3) 5.6 m. 4) 6.5 m. 5) none of these
ANS: 1
ANS: 1
32. How many grams are there in 5.5 moles of potassium phosphate?
1) 212.3 grams 2) 398.6 grams 3) 952.6 grams 4) 1,167.7 grams
ANS: 4
33. Calculate the mass of 6.3 moles of ammonium sulfate.
1) 945.0 grams 2) 832.2 grams 3) 718.2 grams 4) 646.4 grams
ANS: 2
34. How many grams are there in 3.5 moles of (NH4)2CO3?
1) 27.4
grams 2) 78.4 grams 3) 273.0 grams 4) 336.0 grams
ANS: 4
35. Calculate the mass of 6.3 moles of lead
phosphate.
1) 128.8
grams 2) 1,903.9 grams 3) 2,142.0 grams 4) 5,113.1 grams
ANS: 4
36. How many moles are there in 446 grams of calcium
bicarbonate?
1) 0.4
mole 2) 2.8 moles 3) 4.4 moles 4) 7.7 moles
ANS: 2
37. How many moles are there in 260 grams of
magnesium iodide?
1) 0.9
mole 2) 1.1 moles 3) 1.7 moles 4) 3.3 moles
ANS: 1
38. How many moles of nitrogen are there in 55.5
grams of this gas?
1) 0.5
mole 2) 1.6 moles 3) 2.0 moles 4) 4.0 moles
ANS: 3
39. Calculate the mass of 0.14 mole of sodium atoms.
1) 1.4
grams 2) 3.2 grams 3) 76.0 grams 4) 164.3 grams
ANS: 2
40. How many grams are there in 0.6 mole of aluminum
carbonate?
1) 52.2 grams 2) 88.2 grams 3) 120.6 grams 4) 140.4 grams
ANS: 4
41. How many grams are there in 0.08 mole of cupric
acetate?
1) 9.8
grams 2) 12.2 grams 3) 14.5 grams 4) 14.9 grams
ANS: 3
42. A compound whose empirical
(simplest) formula is CH2 has a molecular mass of 28.
What is the molecular formula? 1) CH2 2) C2H4 3) C2H2 4) CH4
ANS: 2
43. A compound contains 0.5 mole of sodium, 0.5 mole of nitrogen, and 1.0
mole of
hydrogen. What is the empirical formula for this
compound?
1) NaNH 2) Na2NH 3) NaNH2
4) NaN2H2
5) Na2N2H
ANS: 3
44. A gas has a density of
0.717 g/l at STP. What is the mass of
one mole of this gas?
1) 8.0 g. 2) 16.1 g. 3) 28.1 g. 4) 4.0 g.
ANS: 2
45. The molecular mass of CO2
is 44; therefore, at STP 1) 1 liter
of CO2 weighs
44 g; 2) 11.2 liters of CO2 weigh
22 g; 3) the molar volume of
CO2 is 44
liters; 4) 22.4 g. of CO2 have a volume of 44 liters.
ANS: 2
46. At STP 1.0 liter of an oxide of N weighs approximately 2.05
grams.
Identify this
compound. 1) N2O 2) NO2 3) NO 4) N2O3
ANS: 2
47. A liter of a certain gas weighs 1.63 grams at S.T.P. The mass of one
mole of this
gas is
1) 1.63 g; 2) more than 1.63
but less than 2 g; 3) 22.4 g; 4) 36.5 g.
ANS: 4
48. At STP the mass of 1 liter of a gas is 1.17 grams. The gas might be:
1) CO2; 2) CN; 3) CO; 4) NO.
ANS: 2
49. Which gas has the greatest
density at standard temperature and pressure?
1) nitrogen 2) oxygen 3) chlorine 4) fluorine
ANS: 3
50. A liter of a certain gas weighs 1.25 grams at STP. The mass of one mole of this gas is
1) 1.25 g.; 2) a little less than 1.0 g.; 3) 22.4 g.; 4) 28 g.; 5) 11.2 g.
ANS: 4
51. Find the mass of 3.9 x 1023 molecules of carbon dioxide
gas at STP conditions.
1) 19.1 grams 3) 67.7 grams
2) 28.6 grams 4) 76.4 grams 5) none of these
2) 28.6 grams 4) 76.4 grams 5) none of these
ANS: 2
52. How many grams of oxygen at
STP contain the same number of molecules as
14 grams of nitrogen at STP? 1) 14 g. 2) 16 g. 3) 28 g. 4) 32 g.
ANS: 2
53. What is the mass of 11.2
liters of nitrogen at standard temperature and pressure?
1) 7.0 g. 2) 14.0 g. 3) 22.4 g. 4) 28.0 g.
ANS: 2
54. A chemist collected 13.0 grams of acetylene gas, C2H2,
at S.T.P. The approximate
volume occupied by this gas was
1) 5.6 liters; 2) 11.2 liters; 3) 22.4 liters; 4) 44.8 liters.
ANS: 2
55. What is the volume of 8.0 grams of sulfur dioxide, SO2, at
STP ?
1) 2.80 liters 2) 5.60 liters 3) 11.2 liters 4) 22.4 liters
ANS: 1
56. What is the molecular mass of a gas whose density at STP is 1.78
grams/liter ?
1) 1.78 grams/mole 3) 22.4 grams/mole
2) 13.3 grams/mole 4) 39.9 grams/mole 5) 79.8 grams/mole
2) 13.3 grams/mole 4) 39.9 grams/mole 5) 79.8 grams/mole
ANS: 4
57. Under standard conditions, the mass of one liter of a gas with a
molecular mass of
32 is 1) 1.43; 2) 16.0; 3) 22.4; 4) 32.0;
5) none of these.
ANS: 1
58. The volume of 16.0 grams of oxygen at standard temperature and pressure
is
1) 1 liter; 2) 11.2 liters; 3) 16.0 liters; 4) 22.4 liters.
ANS: 2
59. Under standard conditions, 22.4 liters of
nitrogen have the same mass as
22.4 liters
of 1) NH3; 2) CO; 3) Cl2; 4) O2.
ANS: 2
60. What is the mass of one liter of acetylene, C2H2,
at standard temperature
and
pressure? 1) 0.94 g. 2) 1.16 g. 3) 2.47 g. 4) 12.3 g.
ANS: 2
61. Under standard conditions,
the mass of 22.4 liters of carbon monoxide is
1) 14 grams; 2) 20 grams; 3) 22.5 grams; 4) 28 grams.
ANS: 4
62. Calculate the mass of 25.0 liters of oxygen when the volume is measured
at S.T.P.
1) 35.7 grams 2) 44.8 grams 3) 56.0 grams 4) 72.0 grams
5) none of these
ANS: 1
63. Calculate the mass of 4.0
liters of carbon dioxide at S.T.P.
1) 7.9 grams 2) 11.2 grams 3) 16 grams 4) 44.0 grams
ANS: 1
64. A liter of a certain gas weighs 2.86 grams at
S.T.P. The mass of one mole of
this gas
is 1) 2.86 g; 2) more than 2.86 g. but less than 4
g; 3) 22.4 g;
4) 32
g.; 5) 64 g.
ANS: 5
65. What is the mass of 50.0 liters of oxygen gas, O2, at
S.T.P. ?
1) 32.0 grams 2) 71.4 grams 3) 100 grams 4) 143 grams
ANS:2
66. At S.T.P., what volume does
1.00 gram of hydrogen, H2, occupy?
1) 1.00 liter 2) 2.80 liters 3) 5.60 liters 4) 11.2 liters 5) 22.4 liters
ANS: 4
67. Under standard conditions,
the mass of one liter of a gas with a molecular mass of 42 is
1) l.87 grams; 2) 10.5 grams; 3) 16.0 grams; 4) 22.4 grams; 5) 42 grams.
ANS: 1
68. At S.T.P. conditions what will 112 liters of ammonia,
NH3, weigh?
1) 3.4
grams 2) 67.2 grams 3) 85.0 grams 4) 147.6 grams
ANS: 3
69. What is the volume of 32 grams of sulfur dioxide,
SO2, at S.T.P. conditions?
1) 11.2 liters 2) 22.4 liters 3) 44.8 liters 4) 91.4 liters
ANS: 1
70. All gases
1) condense at the same temperature.
2) have the same density at
equal temperatures and pressures.
3) possess volumes that are
proportional to the temperature above 00C.
4) possess a volume of 22.4
1/mole at 00C and one atmospheric pressure.
ANS: 4
71. How many moles of carbon dioxide are present in 550
liters at 00C and one atmosphere
of pressure? l) 0.04 m. 2) 13.8 m. 3) 24.6 m. 4) 123.2 m. 5) none of these
ANS: 3
72. If 375 liters of hydrogen are at 00C and 1 atmosphere
pressure, how many moles
are present of
this gas?
1) 0.06 m. 2) 16.7 m. 3) 43.5 m. 4) 840.0 m. 5) none of these
1) 0.06 m. 2) 16.7 m. 3) 43.5 m. 4) 840.0 m. 5) none of these
ANS: 2
73. The volume occupied by 2 moles of hydrogen at standard
temperature and pressure is
1) 1.0 liter; 2) 22.4 liters; 3) 11.2 liters; 4) 33.6 liters; 5) 44.8 liters.
ANS: 5
74. The volume occupied by 3 moles of oxygen at standard temperature and
pressure
is 1) 1.0 liter; 2) 22.4 liters; 3) 3 liters; 4) 67.2 liters.
ANS: 4
75. What is the volume of 0.50
mole of carbon dioxide gas, CO2. measured at S.T.P.?
1) 5.6 liters 2) 11.2 liters 3) 33.6 liters 4) 44.8 liters
ANS: 2
76. How many moles are present when 340 liters of a
gas are at S.T.P. conditions?
1) 0.07
mole 2) 2.18 moles 3) 8.07 moles 4) 15.20 moles
ANS: 4
77. According to Avogadro’s hypothesis, the simplest molecule of
hydrogen contains
1) 1 atom; 2) 2 atoms; 3) 22.4 atoms; 4) 32 atoms; 5) 6 x 1023 atoms.
ANS: 2
78. Avogadro’s number, 6.02 x
1023, indicates
1) the amount of charge on an
electron.
2) the
number of particles in a mole of particles.
3) a
comparison of the mass of the proton and the electron.
.
4) the weight of 1 atomic mass unit.
ANS: 2
79. The number of molecules in a mole of any molecular substance compared
to the
number of atoms
in one mole of any element is 1)
always larger; 2) always less;
3) sometimes larger and
sometimes smaller; 4) always the
same; 5) varies
with the
substance.
ANS: 4
80. Which sample contains the same number of atoms as 24 grams of carbon?
1) 80 g. Ar 2) 24 g. Mg 3) 10 g. Ne 4) 4 g. He 5) 197 g. Au
ANS: 1
81. Calculate the mass of 4.7 x 1022 molecules of lead iodide.
1) 36.1 grams 3) 249.0 grams
2) 108.3 grams 4) 697.3 grams 5) 5,885 grams
2) 108.3 grams 4) 697.3 grams 5) 5,885 grams
ANS: 1
82. How many molecules are present in a 6.0 gram sample of carbon
dioxide, CO2?
1) 6.0 2) 6.02 x 1023
3) 6 x 6.02 x 1023
4) _ 44.0___
44.0 44.0 6.02 x 1023
ANS: 3
83. There are 6.02 x 1023
water molecules in a mole of water. What is the mass
of 3.01 x 1023 molecules of
water?
1) 0.50 grams 3) 18.0 grams
2) 9.00 grams 4) 27.0 grams 5) 36.0 grams
2) 9.00 grams 4) 27.0 grams 5) 36.0 grams
ANS: 2
84. If 8.6 x 1023
molecules of calcium hydroxide are present, what will be
the reading on a balance?
1) 25.8 grams 3) 74.2 grams
2) 51.6 grams 4) 87.8 grams 5) 106.2 grams
1) 25.8 grams 3) 74.2 grams
2) 51.6 grams 4) 87.8 grams 5) 106.2 grams
ANS: 5
85. What volume of hydrogen sulfide gas, H2S, has the same
number of molecules as
10.0 liters of neon gas,
Ne? Both gases are at the same
temperature and pressure.
1) 3.33 liters 2) 10.0 liters 3) 22.4 liters 4) 30.0 liters
ANS: 2
86. A two gram sample of which element contains the
greatest number of atoms?
1) Al 2) Na 3) P 4) S 5) Be
ANS: 5
87. Calculate the moles of silver oxide in 1.4 x 1025
molecules of this compound.
1) 0.043 mole 3) 16.9 moles
2) 1.86 moles 4) 23.3 moles 5) none of these
2) 1.86 moles 4) 23.3 moles 5) none of these
ANS: 4
88. How many moles of tin are there in 4.63 x 1023 atoms of
this element?
1) 0.35 mole 2) 0.52 mole 3) 0.77 mole 4) 1.24 moles 5) 1.66 moles
ANS: 3
89. How many moles are present
for 6.8 x 1024 molecules of barium phosphate?
1) 0.088 mole 3) 1.18 moles
2) 0.264 mole 4) 9.80 moles 5) 11.30 moles
1) 0.088 mole 3) 1.18 moles
2) 0.264 mole 4) 9.80 moles 5) 11.30 moles
ANS: 5
90. A mole of sulfur dioxide
gas and a mole of carbon monoxide gas always have the
same
1) mass; 2) pressure; 3) number of atoms; 4) number of molecules.
ANS: 4
91. Under the same conditions of temperature and pressure, a liter of
hydrogen compared to a liter of
oxygen contains
1) more molecules than the
liter of oxygen.
2) fewer molecules than the liter of
oxygen.
3) the same number of molecules as the
liter of oxygen.
4) the same total mass of gas as the liter
of oxygen.
ANS: 3
92. One liter of hydrogen and
one liter of oxygen
1) react completely with each other. 3) possess the same total amount
of energy.
2) contain the same number of molecules. 4) will combine to form one liter of
water.
ANS: 2
93. Calculate the molecules present in 125 liters of methane at STP
conditions.
1) 1.1 x 1023 3) 3.9 x 1024
2) 3.3 x 1024 4) 9.2 x 1024 5) 8.7 x 1023
2) 3.3 x 1024 4) 9.2 x 1024 5) 8.7 x 1023
ANS: 2
94. Eighty-five liters of an unknown gas contain how many molecules at
standard temperature and
pressure conditions?
1) 1.6 x 1024 3) 5.5 x 1024
1) 1.6 x 1024 3) 5.5 x 1024
2) 2.3 x 1024 4) 1.1 x 1025 5) none of these
ANS: 2
95. One liter of oxygen at STP contains approximately the same number of
molecules
as 1) 2 liters of He at STP; 2) 1/3 liter of O3 at STP; 3) 1 liter of CO2
at STP; 4) 1/5 liter of CH4 at STP.
ANS: 3
96. If 500 grams of a gas
contain 7.6 x 1023 molecules, what will be the volume of
this gas
at STP conditions?
1) 17.7 liters 3) 28.4 liters
2) 24.5 liters 4) 31.2 liters 5) none of these
1) 17.7 liters 3) 28.4 liters
2) 24.5 liters 4) 31.2 liters 5) none of these
ANS: 3
97. How much space will 5.5 x 1020 molecules of oxygen occupy at STP conditions?
1) 2.1 x 10-2 1iters 2) 6.8 x 10-1 liters 3) 1.5 x 103 liters 4) 2.4 x l04 liters
ANS: 1
98. What will be the volume
of 2.6 x 1024 molecules of oxygen at 00C
temperature
and 1 atmosphere pressure?
1) 7.0 liters 2) 37.7 liters 3) 51.7 liters 4) 97.1 liters 5) none of these
ANS: 4
99. How many molecules are there in 176.5 liters of ammonia, NH3? This gas is at
S.T.P. conditions.
1) 6.6 x 1021 2) 7.6 x 1022 3) 4.3 x 1023 4) 4.7 x 1024
ANS: 4
100. If a sealed flask contains
3 x 1026 nitrogen dioxide
molecules, how many moles
of this gas are in the flask?
1) 1 x 1023 m. 2) 1 x 103 m. 3) 0.5 x 103 m. 4) 2 x 103 m.
ANS: 3
101. A sample of Ne contains 1.0 x 1023 molecules. How many
molecules will an
equal volume of H2
contain at the same temperature and pressure conditions?
1) 1.0 x 1023 2) 2.0 x 1023 3) 3.0 x 1023 4) 6.0 x 1023 5) none of these
ANS: 1
102. Equal volumes of all gases, under the same conditions of temperature
and pressure,
contain an equal
number of 1) atoms; 2) molecules; 3) electrons; 4) grams;
5) none of these.
ANS: 2
103. Calculate the number of molecules in 77.7 liters of hydrogen when
this gas
is at S.T.P. conditions.
1) 2.9 x 1021
molecules 3) 1.7 x 1023
molecules
2) 8.3 x 1022
molecules 4) 2.1 x 1024
molecules 5) none
of these
ANS: 4
104. If 106 liters of nitrogen
are at STP conditions, how many gas molecules are present?
1) 4.0
x 1021 molecules
3) 2.8 x 1024 molecules
2) 1.3 x 1023 molecules 4) 6.1 x 1024 molecules 5) none of these
2) 1.3 x 1023 molecules 4) 6.1 x 1024 molecules 5) none of these
ANS: 3
105. At standard temperature and pressure, how much space should 7.5 x 1022
molecules
of sulfur
dioxide take up?
1) 2.8 liters 3) 32.4 liters
2) 17.9 liters 4) 74.4 liters 5) 179.0 liters
1) 2.8 liters 3) 32.4 liters
2) 17.9 liters 4) 74.4 liters 5) 179.0 liters
ANS: 1
106. Determine the molecular count of a 480 liter sample of gas at standard
temperature
and pressure.
1) 2.8 x 1022 3) 1.4 x 1024
2) 6.9 x 1023 4) 1.3 x 1025 5) 2.4 x 1025
1) 2.8 x 1022 3) 1.4 x 1024
2) 6.9 x 1023 4) 1.3 x 1025 5) 2.4 x 1025
ANS: 4
107. How many molecules are present in 50.0 liters of a gas at STP
conditions?
1) 2.7 x 1023 3) 1.3 x 1024
2) 8.1 x 1023 4) 1.6 x 1024 5) none of these
2) 8.1 x 1023 4) 1.6 x 1024 5) none of these
ANS: 3
108. How many liters are present when
8.1 x 1022 molecules
of carbon monoxide are
at 00C. and 1.0
atmosphere pressure?
1) 3.0 liters 2) 7.5 liters 3) l1.8 liters 4) 16.5 liters 5) none of these
ANS: 1
109. At standard temperature and pressure, what volume will 3.2 x 1024
molecules of
SO3
occupy? 1) 4.2 liters 2) 42.0 liters 3) 46.2 liters 4) 66.7 liters
5) 119.0
liters
ANS: 5
110. Oxygen and hydrogen differ in 1) color; 2) odor; 3) taste; 4) density.
ANS: 4
111. The mass of hydrogen in 34
grams of ammonia, NH3, is
1) 1 gram; 2) 3 grams; 3) 6 grams; 4) 17 grams.
ANS: 3
CHEMISTRY TEST NAME: _____________________
THE MOLE CONCEPT
DATE: _____________________
Directions: For each of the following questions, choose the
number that best answers the question and place it on your answer sheet.
Directions: For each of the following questions, all major
steps must be shown to receive
full credit.
The Mole Concept
Level 1
Multiple Choice
1. The sample of oxygen at S.T.P. which represents the greatest mass is one
1) mole; 2) gram; 3) molecule; 4) liter.
ANS: 1
2. The mass of a mole of a gas
divided by 22.4 liters equals 1) the
density of the gas
at STP; 2) the volume of the gas; 3) the empirical formula of the
gas;
4) the volume of 6.02 x 1023 molecules of the gas.
ANS: 1
3. The formula for one molecule of hydrogen is
1) H2; 2) 2 H; 3) 2 H+; 4) 2 H-; 5) none of these.
ANS: 1
4. The formula CO2 does
not give information about
1) the elements which make up
the compound.
2) the number of atoms of each
element in the compound.
3) the solubility of the
compound in water.
4) the relative mass of the
molecule.
ANS: 3
5. The molecular formula H2O represents all of the following except 1) one molecule
of water; 2) the relative number of atoms in a
molecule; 3) one formula mass
of water; 4) one gram of water; 5) one mole of water.
ANS: 4
6. The atomic mass of Mg is 24,
and the atomic mass of Cl is 35.5. One
mole of MgCl2
1) represents 95 molecules of the compound. 3) contains 35.5 molecules of chlorine.
2) represents 95 grams of the compound. 4) contains 2 moles of chlorine
molecules.
ANS: 2
7. If two containers of different gases under the same conditions have
the same number
of molecules, the gases must
have 1) an equal number of
atoms; 2) equal
molecular
masses; 3) equal volumes; 4) equal masses.
ANS: 3
8. How many mole(s) of calcium carbonate is represented by 50 grams of
the compound?
1) 1.0 m. 2) 2.0 m. 3) 0.20 m. 4) 4.0 m. 5) 0.50 m.
1) 1.0 m. 2) 2.0 m. 3) 0.20 m. 4) 4.0 m. 5) 0.50 m.
ANS: 5
9. How many moles are there in 120 grams of neon?
1) 2.4 moles 2) 4.2 moles 3) 6.0 moles 4) 10.0 moles
ANS: 3
10. The mass of one mole of ammonium carbonate is approximately
1) 43.0 g; 2) 72.0 g; 3) 78.0 g; 4) 96.0 g; 5) none of these.
ANS: 4
11. What is the mass of 3.4
moles of aluminum hydroxide?
1) 156.4 g. 2) 207.4 g. 3) 265.2 g. 4) 294.1 g.
ANS: 3
12. How many grams are there in 0.85 moles of iodine?
1) 48 g. 2) 108 g. 3) 127 g. 4) none of these
ANS: 4
13. What is the mass of one mole of tin (II) fluoride?
1) 59.0 g. 2) 68.0 g. 3) 138 g. 4) 157 g. 5) 126 g.
ANS: 4
14. A liter of a certain gas weighs 1.25 grams at
S.T.P. The mass of one mole of this
gas is 1) 1.25 g; 2) 22.4 g; 3) between 1.25 and 2.0 g; 4) 28 g; 5) 32 g.
ANS: 4
15. Which sample contains the same number of atoms as 24 grams of carbon?
1) 80 gram Ar 2) 24 gram Mg 3) 10 gram Ne 4) 4.0 gram He
ANS: 1
16. What is the number of moles
present in 862 grams of calcium hydrogen sulfate?
1) 6.3 moles 2) 5.2 moles 3) 3.7 moles 4) 4.1 moles 5) none of these
ANS: 3
17. The mass of 1 mole of CaSO4.2H2O
is 1) 11 g; 2) 154 g; 3) 172 g;
4) 200 g; 5) 217 g.
ANS: 3
18. What is the mass of one
mole of the gasoline additive lead tetraethyl, Pb(C2H5)4?
1) 323 g. 2) 251 g. 3) 236 g. 4) 150 g.
ANS: 1
19. What is the approximate
mass of a mole of carbon tetrachloride, CCl4?
1) 1.00 gram 2) 22.4 grams 3) 47.5 grams 4) 83.5 grams 5) 154 grams
ANS: 5
20. In one gram-molecular mass
of copper (II) sulfate, the total mass of oxygen is
1) 16 grams; 2) 48 grams; 3) 64 grams; 4) 144 grams.
ANS: 3
21. How many moles are there in 75 grams of calcium?
1) 1.9 moles 2) 2.4 moles 3) 4.2 moles 4) 40 moles 5) none of these
ANS: 1
1) 1.9 moles 2) 2.4 moles 3) 4.2 moles 4) 40 moles 5) none of these
ANS: 1
22. How many moles are there in
100 grams of the element helium?
1) 12.5 m. 2) 25.0 m. 3) 50.0 m. 4) 100 m. 5) 400 m.
1) 12.5 m. 2) 25.0 m. 3) 50.0 m. 4) 100 m. 5) 400 m.
ANS: 2
23. What is the mass of 3.4 moles of chromic dichromate?
1) 207.4 g. 2) 394.8 g. 3) 752.0 g. 4) 911.2 g. 5) 2,556.8 g.
ANS: 5
24. How many moles of hydrogen
cyanide, HCN, are contained in 9.00 grams of HCN?
1) 0.090 m. 2) 0.333 m. 3) 1.00 m. 4) 9.00 m.
ANS: 2
25. How many grams are there in 1.5 moles of zinc?
1) 15 grams 2) 47 grams 3) 65 grams 4) 98 grams
ANS: 4
26. Calculate the number of moles in 400 grams of mercuric hydroxide.
1) 1.71 moles 2) 1.84 moles 3) 2.40 moles 4) 3.10 moles
ANS: 1
27. How many moles are there in 600.0 grams of sodium dichromate?
1) 1.6 m. 2) 2.3 m. 3) 3.1 m. 4) 3.7 m. 5) none of these
ANS: 2
28. The number of moles of sodium chloride represented by 117 grams is
1) 1 m; 2) 2 m; 3) 3 m; 4) 3.25 m; 5) 22.4 m.
ANS: 2
29. Calculate the mass of 3.0
moles of ethyl alcohol, C2H5OH.
1) 46
grams 2) 69 grams 3) 82 grams 4) 118 grams 5) 138 grams
ANS: 5
30. What is the mass of two
moles of calcium chloride?
1) 80
grams 2) 151 grams 3) 202 grams 4) 222 grams 5) 231 grams
ANS: 4
31. Calculate the number of moles in 800 grams of aluminum sulfate.
1) 2.3 m. 2) 2.9 m. 3) 5.6 m. 4) 6.5 m. 5) none of these
ANS: 1
ANS: 1
32. How many grams are there in 5.5 moles of potassium phosphate?
1) 212.3 grams 2) 398.6 grams 3) 952.6 grams 4) 1,167.7 grams
ANS: 4
33. Calculate the mass of 6.3 moles of ammonium sulfate.
1) 945.0 grams 2) 832.2 grams 3) 718.2 grams 4) 646.4 grams
ANS: 2
34. How many grams are there in 3.5 moles of (NH4)2CO3?
1) 27.4
grams 2) 78.4 grams 3) 273.0 grams 4) 336.0 grams
ANS: 4
35. Calculate the mass of 6.3 moles of lead
phosphate.
1) 128.8
grams 2) 1,903.9 grams 3) 2,142.0 grams 4) 5,113.1 grams
ANS: 4
36. How many moles are there in 446 grams of calcium
bicarbonate?
1) 0.4
mole 2) 2.8 moles 3) 4.4 moles 4) 7.7 moles
ANS: 2
37. How many moles are there in 260 grams of
magnesium iodide?
1) 0.9
mole 2) 1.1 moles 3) 1.7 moles 4) 3.3 moles
ANS: 1
38. How many moles of nitrogen are there in 55.5
grams of this gas?
1) 0.5
mole 2) 1.6 moles 3) 2.0 moles 4) 4.0 moles
ANS: 3
39. Calculate the mass of 0.14 mole of sodium atoms.
1) 1.4
grams 2) 3.2 grams 3) 76.0 grams 4) 164.3 grams
ANS: 2
40. How many grams are there in 0.6 mole of aluminum
carbonate?
1) 52.2 grams 2) 88.2 grams 3) 120.6 grams 4) 140.4 grams
ANS: 4
41. How many grams are there in 0.08 mole of cupric
acetate?
1) 9.8
grams 2) 12.2 grams 3) 14.5 grams 4) 14.9 grams
ANS: 3
42. A compound whose empirical
(simplest) formula is CH2 has a molecular mass of 28.
What is the molecular formula? 1) CH2 2) C2H4 3) C2H2 4) CH4
ANS: 2
43. A compound contains 0.5 mole of sodium, 0.5 mole of nitrogen, and 1.0
mole of
hydrogen. What is the empirical formula for this
compound?
1) NaNH 2) Na2NH 3) NaNH2
4) NaN2H2
5) Na2N2H
ANS: 3
44. A gas has a density of
0.717 g/l at STP. What is the mass of
one mole of this gas?
1) 8.0 g. 2) 16.1 g. 3) 28.1 g. 4) 4.0 g.
ANS: 2
45. The molecular mass of CO2
is 44; therefore, at STP 1) 1 liter
of CO2 weighs
44 g; 2) 11.2 liters of CO2 weigh
22 g; 3) the molar volume of
CO2 is 44
liters; 4) 22.4 g. of CO2 have a volume of 44 liters.
ANS: 2
46. At STP 1.0 liter of an oxide of N weighs approximately 2.05
grams.
Identify this
compound. 1) N2O 2) NO2 3) NO 4) N2O3
ANS: 2
47. A liter of a certain gas weighs 1.63 grams at S.T.P. The mass of one
mole of this
gas is
1) 1.63 g; 2) more than 1.63
but less than 2 g; 3) 22.4 g; 4) 36.5 g.
ANS: 4
48. At STP the mass of 1 liter of a gas is 1.17 grams. The gas might be:
1) CO2; 2) CN; 3) CO; 4) NO.
ANS: 2
49. Which gas has the greatest
density at standard temperature and pressure?
1) nitrogen 2) oxygen 3) chlorine 4) fluorine
ANS: 3
50. A liter of a certain gas weighs 1.25 grams at STP. The mass of one mole of this gas is
1) 1.25 g.; 2) a little less than 1.0 g.; 3) 22.4 g.; 4) 28 g.; 5) 11.2 g.
ANS: 4
51. Find the mass of 3.9 x 1023 molecules of carbon dioxide
gas at STP conditions.
1) 19.1 grams 3) 67.7 grams
2) 28.6 grams 4) 76.4 grams 5) none of these
2) 28.6 grams 4) 76.4 grams 5) none of these
ANS: 2
52. How many grams of oxygen at
STP contain the same number of molecules as
14 grams of nitrogen at STP? 1) 14 g. 2) 16 g. 3) 28 g. 4) 32 g.
ANS: 2
53. What is the mass of 11.2
liters of nitrogen at standard temperature and pressure?
1) 7.0 g. 2) 14.0 g. 3) 22.4 g. 4) 28.0 g.
ANS: 2
54. A chemist collected 13.0 grams of acetylene gas, C2H2,
at S.T.P. The approximate
volume occupied by this gas was
1) 5.6 liters; 2) 11.2 liters; 3) 22.4 liters; 4) 44.8 liters.
ANS: 2
55. What is the volume of 8.0 grams of sulfur dioxide, SO2, at
STP ?
1) 2.80 liters 2) 5.60 liters 3) 11.2 liters 4) 22.4 liters
ANS: 1
56. What is the molecular mass of a gas whose density at STP is 1.78
grams/liter ?
1) 1.78 grams/mole 3) 22.4 grams/mole
2) 13.3 grams/mole 4) 39.9 grams/mole 5) 79.8 grams/mole
2) 13.3 grams/mole 4) 39.9 grams/mole 5) 79.8 grams/mole
ANS: 4
57. Under standard conditions, the mass of one liter of a gas with a
molecular mass of
32 is 1) 1.43; 2) 16.0; 3) 22.4; 4) 32.0;
5) none of these.
ANS: 1
58. The volume of 16.0 grams of oxygen at standard temperature and pressure
is
1) 1 liter; 2) 11.2 liters; 3) 16.0 liters; 4) 22.4 liters.
ANS: 2
59. Under standard conditions, 22.4 liters of
nitrogen have the same mass as
22.4 liters
of 1) NH3; 2) CO; 3) Cl2; 4) O2.
ANS: 2
60. What is the mass of one liter of acetylene, C2H2,
at standard temperature
and
pressure? 1) 0.94 g. 2) 1.16 g. 3) 2.47 g. 4) 12.3 g.
ANS: 2
61. Under standard conditions,
the mass of 22.4 liters of carbon monoxide is
1) 14 grams; 2) 20 grams; 3) 22.5 grams; 4) 28 grams.
ANS: 4
62. Calculate the mass of 25.0 liters of oxygen when the volume is measured
at S.T.P.
1) 35.7 grams 2) 44.8 grams 3) 56.0 grams 4) 72.0 grams
5) none of these
ANS: 1
63. Calculate the mass of 4.0
liters of carbon dioxide at S.T.P.
1) 7.9 grams 2) 11.2 grams 3) 16 grams 4) 44.0 grams
ANS: 1
64. A liter of a certain gas weighs 2.86 grams at
S.T.P. The mass of one mole of
this gas
is 1) 2.86 g; 2) more than 2.86 g. but less than 4
g; 3) 22.4 g;
4) 32
g.; 5) 64 g.
ANS: 5
65. What is the mass of 50.0 liters of oxygen gas, O2, at
S.T.P. ?
1) 32.0 grams 2) 71.4 grams 3) 100 grams 4) 143 grams
ANS:2
66. At S.T.P., what volume does
1.00 gram of hydrogen, H2, occupy?
1) 1.00 liter 2) 2.80 liters 3) 5.60 liters 4) 11.2 liters 5) 22.4 liters
ANS: 4
67. Under standard conditions,
the mass of one liter of a gas with a molecular mass of 42 is
1) l.87 grams; 2) 10.5 grams; 3) 16.0 grams; 4) 22.4 grams; 5) 42 grams.
ANS: 1
68. At S.T.P. conditions what will 112 liters of ammonia,
NH3, weigh?
1) 3.4
grams 2) 67.2 grams 3) 85.0 grams 4) 147.6 grams
ANS: 3
69. What is the volume of 32 grams of sulfur dioxide,
SO2, at S.T.P. conditions?
1) 11.2 liters 2) 22.4 liters 3) 44.8 liters 4) 91.4 liters
ANS: 1
70. All gases
1) condense at the same temperature.
2) have the same density at
equal temperatures and pressures.
3) possess volumes that are
proportional to the temperature above 00C.
4) possess a volume of 22.4
1/mole at 00C and one atmospheric pressure.
ANS: 4
71. How many moles of carbon dioxide are present in 550
liters at 00C and one atmosphere
of pressure? l) 0.04 m. 2) 13.8 m. 3) 24.6 m. 4) 123.2 m. 5) none of these
ANS: 3
72. If 375 liters of hydrogen are at 00C and 1 atmosphere
pressure, how many moles
are present of
this gas?
1) 0.06 m. 2) 16.7 m. 3) 43.5 m. 4) 840.0 m. 5) none of these
1) 0.06 m. 2) 16.7 m. 3) 43.5 m. 4) 840.0 m. 5) none of these
ANS: 2
73. The volume occupied by 2 moles of hydrogen at standard
temperature and pressure is
1) 1.0 liter; 2) 22.4 liters; 3) 11.2 liters; 4) 33.6 liters; 5) 44.8 liters.
ANS: 5
74. The volume occupied by 3 moles of oxygen at standard temperature and
pressure
is 1) 1.0 liter; 2) 22.4 liters; 3) 3 liters; 4) 67.2 liters.
ANS: 4
75. What is the volume of 0.50
mole of carbon dioxide gas, CO2. measured at S.T.P.?
1) 5.6 liters 2) 11.2 liters 3) 33.6 liters 4) 44.8 liters
ANS: 2
76. How many moles are present when 340 liters of a
gas are at S.T.P. conditions?
1) 0.07
mole 2) 2.18 moles 3) 8.07 moles 4) 15.20 moles
ANS: 4
77. According to Avogadro’s hypothesis, the simplest molecule of
hydrogen contains
1) 1 atom; 2) 2 atoms; 3) 22.4 atoms; 4) 32 atoms; 5) 6 x 1023 atoms.
ANS: 2
78. Avogadro’s number, 6.02 x
1023, indicates
1) the amount of charge on an
electron.
2) the
number of particles in a mole of particles.
3) a
comparison of the mass of the proton and the electron.
.
4) the weight of 1 atomic mass unit.
ANS: 2
79. The number of molecules in a mole of any molecular substance compared
to the
number of atoms
in one mole of any element is 1)
always larger; 2) always less;
3) sometimes larger and
sometimes smaller; 4) always the
same; 5) varies
with the
substance.
ANS: 4
80. Which sample contains the same number of atoms as 24 grams of carbon?
1) 80 g. Ar 2) 24 g. Mg 3) 10 g. Ne 4) 4 g. He 5) 197 g. Au
ANS: 1
81. Calculate the mass of 4.7 x 1022 molecules of lead iodide.
1) 36.1 grams 3) 249.0 grams
2) 108.3 grams 4) 697.3 grams 5) 5,885 grams
2) 108.3 grams 4) 697.3 grams 5) 5,885 grams
ANS: 1
82. How many molecules are present in a 6.0 gram sample of carbon
dioxide, CO2?
1) 6.0 2) 6.02 x 1023
3) 6 x 6.02 x 1023
4) _ 44.0___
44.0 44.0 6.02 x 1023
ANS: 3
83. There are 6.02 x 1023
water molecules in a mole of water. What is the mass
of 3.01 x 1023 molecules of
water?
1) 0.50 grams 3) 18.0 grams
2) 9.00 grams 4) 27.0 grams 5) 36.0 grams
2) 9.00 grams 4) 27.0 grams 5) 36.0 grams
ANS: 2
84. If 8.6 x 1023
molecules of calcium hydroxide are present, what will be
the reading on a balance?
1) 25.8 grams 3) 74.2 grams
2) 51.6 grams 4) 87.8 grams 5) 106.2 grams
1) 25.8 grams 3) 74.2 grams
2) 51.6 grams 4) 87.8 grams 5) 106.2 grams
ANS: 5
85. What volume of hydrogen sulfide gas, H2S, has the same
number of molecules as
10.0 liters of neon gas,
Ne? Both gases are at the same
temperature and pressure.
1) 3.33 liters 2) 10.0 liters 3) 22.4 liters 4) 30.0 liters
ANS: 2
86. A two gram sample of which element contains the
greatest number of atoms?
1) Al 2) Na 3) P 4) S 5) Be
ANS: 5
87. Calculate the moles of silver oxide in 1.4 x 1025
molecules of this compound.
1) 0.043 mole 3) 16.9 moles
2) 1.86 moles 4) 23.3 moles 5) none of these
2) 1.86 moles 4) 23.3 moles 5) none of these
ANS: 4
88. How many moles of tin are there in 4.63 x 1023 atoms of
this element?
1) 0.35 mole 2) 0.52 mole 3) 0.77 mole 4) 1.24 moles 5) 1.66 moles
ANS: 3
89. How many moles are present
for 6.8 x 1024 molecules of barium phosphate?
1) 0.088 mole 3) 1.18 moles
2) 0.264 mole 4) 9.80 moles 5) 11.30 moles
1) 0.088 mole 3) 1.18 moles
2) 0.264 mole 4) 9.80 moles 5) 11.30 moles
ANS: 5
90. A mole of sulfur dioxide
gas and a mole of carbon monoxide gas always have the
same
1) mass; 2) pressure; 3) number of atoms; 4) number of molecules.
ANS: 4
91. Under the same conditions of temperature and pressure, a liter of
hydrogen compared to a liter of
oxygen contains
1) more molecules than the
liter of oxygen.
2) fewer molecules than the liter of
oxygen.
3) the same number of molecules as the
liter of oxygen.
4) the same total mass of gas as the liter
of oxygen.
ANS: 3
92. One liter of hydrogen and
one liter of oxygen
1) react completely with each other. 3) possess the same total amount
of energy.
2) contain the same number of molecules. 4) will combine to form one liter of
water.
ANS: 2
93. Calculate the molecules present in 125 liters of methane at STP
conditions.
1) 1.1 x 1023 3) 3.9 x 1024
2) 3.3 x 1024 4) 9.2 x 1024 5) 8.7 x 1023
2) 3.3 x 1024 4) 9.2 x 1024 5) 8.7 x 1023
ANS: 2
94. Eighty-five liters of an unknown gas contain how many molecules at
standard temperature and
pressure conditions?
1) 1.6 x 1024 3) 5.5 x 1024
1) 1.6 x 1024 3) 5.5 x 1024
2) 2.3 x 1024 4) 1.1 x 1025 5) none of these
ANS: 2
95. One liter of oxygen at STP contains approximately the same number of
molecules
as 1) 2 liters of He at STP; 2) 1/3 liter of O3 at STP; 3) 1 liter of CO2
at STP; 4) 1/5 liter of CH4 at STP.
ANS: 3
96. If 500 grams of a gas
contain 7.6 x 1023 molecules, what will be the volume of
this gas
at STP conditions?
1) 17.7 liters 3) 28.4 liters
2) 24.5 liters 4) 31.2 liters 5) none of these
1) 17.7 liters 3) 28.4 liters
2) 24.5 liters 4) 31.2 liters 5) none of these
ANS: 3
97. How much space will 5.5 x 1020 molecules of oxygen occupy at STP conditions?
1) 2.1 x 10-2 1iters 2) 6.8 x 10-1 liters 3) 1.5 x 103 liters 4) 2.4 x l04 liters
ANS: 1
98. What will be the volume
of 2.6 x 1024 molecules of oxygen at 00C
temperature
and 1 atmosphere pressure?
1) 7.0 liters 2) 37.7 liters 3) 51.7 liters 4) 97.1 liters 5) none of these
ANS: 4
99. How many molecules are there in 176.5 liters of ammonia, NH3? This gas is at
S.T.P. conditions.
1) 6.6 x 1021 2) 7.6 x 1022 3) 4.3 x 1023 4) 4.7 x 1024
ANS: 4
100. If a sealed flask contains
3 x 1026 nitrogen dioxide
molecules, how many moles
of this gas are in the flask?
1) 1 x 1023 m. 2) 1 x 103 m. 3) 0.5 x 103 m. 4) 2 x 103 m.
ANS: 3
101. A sample of Ne contains 1.0 x 1023 molecules. How many
molecules will an
equal volume of H2
contain at the same temperature and pressure conditions?
1) 1.0 x 1023 2) 2.0 x 1023 3) 3.0 x 1023 4) 6.0 x 1023 5) none of these
ANS: 1
102. Equal volumes of all gases, under the same conditions of temperature
and pressure,
contain an equal
number of 1) atoms; 2) molecules; 3) electrons; 4) grams;
5) none of these.
ANS: 2
103. Calculate the number of molecules in 77.7 liters of hydrogen when
this gas
is at S.T.P. conditions.
1) 2.9 x 1021
molecules 3) 1.7 x 1023
molecules
2) 8.3 x 1022
molecules 4) 2.1 x 1024
molecules 5) none
of these
ANS: 4
104. If 106 liters of nitrogen
are at STP conditions, how many gas molecules are present?
1) 4.0
x 1021 molecules
3) 2.8 x 1024 molecules
2) 1.3 x 1023 molecules 4) 6.1 x 1024 molecules 5) none of these
2) 1.3 x 1023 molecules 4) 6.1 x 1024 molecules 5) none of these
ANS: 3
105. At standard temperature and pressure, how much space should 7.5 x 1022
molecules
of sulfur
dioxide take up?
1) 2.8 liters 3) 32.4 liters
2) 17.9 liters 4) 74.4 liters 5) 179.0 liters
1) 2.8 liters 3) 32.4 liters
2) 17.9 liters 4) 74.4 liters 5) 179.0 liters
ANS: 1
106. Determine the molecular count of a 480 liter sample of gas at standard
temperature
and pressure.
1) 2.8 x 1022 3) 1.4 x 1024
2) 6.9 x 1023 4) 1.3 x 1025 5) 2.4 x 1025
1) 2.8 x 1022 3) 1.4 x 1024
2) 6.9 x 1023 4) 1.3 x 1025 5) 2.4 x 1025
ANS: 4
107. How many molecules are present in 50.0 liters of a gas at STP
conditions?
1) 2.7 x 1023 3) 1.3 x 1024
2) 8.1 x 1023 4) 1.6 x 1024 5) none of these
2) 8.1 x 1023 4) 1.6 x 1024 5) none of these
ANS: 3
108. How many liters are present when
8.1 x 1022 molecules
of carbon monoxide are
at 00C. and 1.0
atmosphere pressure?
1) 3.0 liters 2) 7.5 liters 3) l1.8 liters 4) 16.5 liters 5) none of these
ANS: 1
109. At standard temperature and pressure, what volume will 3.2 x 1024
molecules of
SO3
occupy? 1) 4.2 liters 2) 42.0 liters 3) 46.2 liters 4) 66.7 liters
5) 119.0
liters
ANS: 5
110. Oxygen and hydrogen differ in 1) color; 2) odor; 3) taste; 4) density.
ANS: 4
111. The mass of hydrogen in 34
grams of ammonia, NH3, is
1) 1 gram; 2) 3 grams; 3) 6 grams; 4) 17 grams.
ANS: 3
