Question 1

Two containers are connected by an open tube. One container (A) is at 300 K, the other (B) is at 600 K. These two containers must have:

Accepted Answer

A)  equal number of moles 
B)  greater pressure in A than B 
C)  greater pressure in B than A 
D)  equal volume 
E)  none of these 
A)  equal number of moles 
B)  greater pressure in A than B 
C)  greater pressure in B than A 
D)  equal volume 
E)  none of these

Question 2

Halothane is one of the modern anesthetics which is nonflammable and relatively safe for patients. What is the molar mass of halothane if 456 milligrams is 52.8 milliliters at 22°C and 805 torr?

Accepted Answer

A)  1.06 × 103 g/mol 
B)  209 g/mol 
C)  197 g/mol 
D)  221 g/mol 
E)  14.7 g/mol 
A)  1.06 × 103 g/mol 
B)  209 g/mol 
C)  197 g/mol 
D)  221 g/mol 
E)  14.7 g/mol

Question 3

A sample of gas has a volume of 2.5 L at 30°C and 720 mmHg. What will be the volume of this gas at 22°C and 750 mmHg?

Accepted Answer

A)  1.8 L 
B)  3.3 L 
C)  2.7 L 
D)  2.3 L 
E)  2.5 L 
A)  1.8 L 
B)  3.3 L 
C)  2.7 L 
D)  2.3 L 
E)  2.5 L

Question 4

A balloon with volume 750 cm3 is filled with O2 at 27°C has a mass of 83.3 g. The mass of empty balloon is 82.1 g. Calculate the pressure of O2.

Accepted Answer

A)  125 kPa 
B)  150 kPa 
C)  250 kPa 
D)  75 kPa 
E)  400 kPa 
A)  125 kPa 
B)  150 kPa 
C)  250 kPa 
D)  75 kPa 
E)  400 kPa

Question 5

Assuming ideal gas behavior, which of the following gases would have the lowest density at standard temperature and pressure?

Accepted Answer

A)  SF6 
B)  CF2Cl2 
C)  CO2 
D)  N2 
E)  Kr 
A)  SF6 
B)  CF2Cl2 
C)  CO2 
D)  N2 
E)  Kr

Question 6

Halothane (CHBrClCF3) is one of the modern anesthetics that is nonflammable and relatively safe for patients. What is the density of halothane in grams per liter at 22°C and 805 torr?

Accepted Answer

A)  8.63 g/L 
B)  7.68 g/L 
C)  6.55 × 103 g/L 
D)  19.3 g/L 
E)  0.130 g/L 
A)  8.63 g/L 
B)  7.68 g/L 
C)  6.55 × 103 g/L 
D)  19.3 g/L 
E)  0.130 g/L

Question 7

Convert to the equivalent pressure in atmospheres, 4.32 × 105 N/m2.

Accepted Answer

A)  4.26 atm 
B)  4.38 × 1010 atm 
C)  4.26 × 103 atm 
D)  3.31 × 105 atm 
E)  0.235 atm 
A)  4.26 atm 
B)  4.38 × 1010 atm 
C)  4.26 × 103 atm 
D)  3.31 × 105 atm 
E)  0.235 atm

Question 8

What is the ratio of the diffusion rates of Cl2 and O2? Rate Cl2 : O2 = _______

Accepted Answer

A)  0.45 
B)  0.69 
C)  0.47 
D)  1.5 
E)  0.67 
A)  0.45 
B)  0.69 
C)  0.47 
D)  1.5 
E)  0.67

Question 9

In which of the following cases is the gas most likely to behave as an ideal gas?

Accepted Answer

A)  H2O(g), 375 K, 750 torr 
B)  He(g), 37.5 K, 7500 torr 
C)  CH4(g), 37.5°C, 7.5 atm 
D)  Ne(g), 375°C, 0.75 atm 
E)  SF6, -37.5°C, 0.75 atm 
A)  H2O(g), 375 K, 750 torr 
B)  He(g), 37.5 K, 7500 torr 
C)  CH4(g), 37.5°C, 7.5 atm 
D)  Ne(g), 375°C, 0.75 atm 
E)  SF6, -37.5°C, 0.75 atm

Question 10

A 5.00 L container of unknown gas at 25.0°C has a pressure of 2.45 atm. The mass of the gas is 32.1 g. What gas is in the container?

Accepted Answer

A)  Cl2 
B)  F2 
C)  NO2 
D)  SO3 
E)  SO2 
A)  Cl2 
B)  F2 
C)  NO2 
D)  SO3 
E)  SO2

Question 11

What is the effusion ratio of uranium-238 to uranium-235?

Accepted Answer

A)  1.000 
B)  0.987 
C)  1.02 
D)  0.994 
E)  1.01 
A)  1.000 
B)  0.987 
C)  1.02 
D)  0.994 
E)  1.01

Question 12

A 34.8 mL sample of an unknown, water-insoluble gas was collected over water at 22.6°C and a barometric pressure of 0.895 atm. When the gas was dried and chilled, it formed 114.6 mg of liquid. What was the molar mass of this substance? [The vapor pressure of water at 22.6°C is 20. mmHg]

Accepted Answer

A)  22.9 g/mol 
B)  38.4 g/mol 
C)  57.3 g/mol 
D)  84.2 g/mol 
E)  92.0 g/mol 
A)  22.9 g/mol 
B)  38.4 g/mol 
C)  57.3 g/mol 
D)  84.2 g/mol 
E)  92.0 g/mol

Question 13

Subtracting the vapor pressure of water from the total pressure of a gas collected over water is an example of the application of:

Accepted Answer

A)  Avogadro's Hypothesis 
B)  Dalton's Law 
C)  Graham's Law 
D)  van der Waals Theory 
E)  ideal gas law 
A)  Avogadro's Hypothesis 
B)  Dalton's Law 
C)  Graham's Law 
D)  van der Waals Theory 
E)  ideal gas law

Question 14

A 4.0 L sample of N2(g) at 760 mmHg is compressed, at constant temperature, to 3.2 atm. What is the final gas volume?

Accepted Answer

A)  950 L 
B)  13 L 
C)  59 L 
D)  1.3 L 
E)  0.77 L 
A)  950 L 
B)  13 L 
C)  59 L 
D)  1.3 L 
E)  0.77 L

Question 15

What mass of water vapor would occupy a volume of 54 L at 200°C and 76 torr, assuming ideal behavior?

Accepted Answer

A)  1.8 g 
B)  2.5 g 
C)  4.3 g 
D)  5.4 g 
E)  7.2 g 
A)  1.8 g 
B)  2.5 g 
C)  4.3 g 
D)  5.4 g 
E)  7.2 g

Question 16

If a liter of CO2 is compared to a liter of H2, both at 25°C and one atmosphere pressure, then:

Accepted Answer

A)  the CO2 and H2 molecules have the same average speed 
B)  there are more H2 molecules than CO2 molecules 
C)  the average kinetic energy of the CO2 molecules is greater than that of the H2 molecules 
D)  the CO2 molecules are, on the average, moving more slowly than the H2 molecules 
E)  the mass of one liter of CO2 equals the mass of one liter of H2 
A)  the CO2 and H2 molecules have the same average speed 
B)  there are more H2 molecules than CO2 molecules 
C)  the average kinetic energy of the CO2 molecules is greater than that of the H2 molecules 
D)  the CO2 molecules are, on the average, moving more slowly than the H2 molecules 
E)  the mass of one liter of CO2 equals the mass of one liter of H2

Question 17

Three volumes of O2 and one volume of CH4 are placed in a sealed container. The temperature and pressure of this mixture are 120°C and 600 kPa. What is the pressure in the same container after the explosion of the mixture and after it was cooled to the initial temperature?

Accepted Answer

A)  350 kPa 
B)  600 kPa 
C)  950 kPa 
D)  750 kPa 
E)  575 kPa 
A)  350 kPa 
B)  600 kPa 
C)  950 kPa 
D)  750 kPa 
E)  575 kPa

Question 18

A 31.4 mL sample of nitrogen gas was collected over water at 23.7°C and a barometric pressure of 706 mmHg. What mass of nitrogen was collected? [The vapor pressure of water at 23.7°C is 22 mmHg.]

Accepted Answer

A)  39.3 mg 
B)  37.7 mg 
C)  34.6 mg 
D)  33.4 mg 
E)  32.5 mg 
A)  39.3 mg 
B)  37.7 mg 
C)  34.6 mg 
D)  33.4 mg 
E)  32.5 mg

Question 19

What volume would be occupied by 4.8 g of oxygen gas at 0.50 atm and 133°C?

Accepted Answer

A)  19 L 
B)  13 L 
C)  10 L 
D)  6.7 L 
E)  3.3 L 
A)  19 L 
B)  13 L 
C)  10 L 
D)  6.7 L 
E)  3.3 L

Question 20

In the reaction Fe2O3 + 3 H2 → 2 Fe + 3 H2O, how many moles of iron can be produced using 17.4 liters of hydrogen at STP?

Accepted Answer

A)  (17.4/22.4)(2/3) mol 
B)  (17.4/22.4)(3/2) mol 
C)  (17.4)(2/3) mol 
D)  (17.4/22.4) mol 
E)  (17.4)(22.4/3) mol 
A)  (17.4/22.4)(2/3) mol 
B)  (17.4/22.4)(3/2) mol 
C)  (17.4)(2/3) mol 
D)  (17.4/22.4) mol 
E)  (17.4)(22.4/3) mol

Exam 6: Gases

Two containers are connected by an open tube. One container (A) is at 300 K, the other (B) is at 600 K. These two containers must have:

Halothane is one of the modern anesthetics which is nonflammable and relatively safe for patients. What is the molar mass of halothane if 456 milligrams is 52.8 milliliters at 22°C and 805 torr?

A sample of gas has a volume of 2.5 L at 30°C and 720 mmHg. What will be the volume of this gas at 22°C and 750 mmHg?

A balloon with volume 750 cm3 is filled with O2 at 27°C has a mass of 83.3 g. The mass of empty balloon is 82.1 g. Calculate the pressure of O2.

Assuming ideal gas behavior, which of the following gases would have the lowest density at standard temperature and pressure?

Halothane (CHBrClCF3) is one of the modern anesthetics that is nonflammable and relatively safe for patients. What is the density of halothane in grams per liter at 22°C and 805 torr?

Convert to the equivalent pressure in atmospheres, 4.32 × 105 N/m2.

What is the ratio of the diffusion rates of Cl2 and O2? Rate Cl2 : O2 = _______

In which of the following cases is the gas most likely to behave as an ideal gas?

A 5.00 L container of unknown gas at 25.0°C has a pressure of 2.45 atm. The mass of the gas is 32.1 g. What gas is in the container?

What is the effusion ratio of uranium-238 to uranium-235?

A 34.8 mL sample of an unknown, water-insoluble gas was collected over water at 22.6°C and a barometric pressure of 0.895 atm. When the gas was dried and chilled, it formed 114.6 mg of liquid. What was the molar mass of this substance? [The vapor pressure of water at 22.6°C is 20. mmHg]

Subtracting the vapor pressure of water from the total pressure of a gas collected over water is an example of the application of:

A 4.0 L sample of N2(g) at 760 mmHg is compressed, at constant temperature, to 3.2 atm. What is the final gas volume?

What mass of water vapor would occupy a volume of 54 L at 200°C and 76 torr, assuming ideal behavior?

If a liter of CO2 is compared to a liter of H2, both at 25°C and one atmosphere pressure, then:

Three volumes of O2 and one volume of CH4 are placed in a sealed container. The temperature and pressure of this mixture are 120°C and 600 kPa. What is the pressure in the same container after the explosion of the mixture and after it was cooled to the initial temperature?

A 31.4 mL sample of nitrogen gas was collected over water at 23.7°C and a barometric pressure of 706 mmHg. What mass of nitrogen was collected? [The vapor pressure of water at 23.7°C is 22 mmHg.]

What volume would be occupied by 4.8 g of oxygen gas at 0.50 atm and 133°C?

In the reaction Fe2O3 + 3 H2 → 2 Fe + 3 H2O, how many moles of iron can be produced using 17.4 liters of hydrogen at STP?

Matter - Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Additional Aspects

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Chemical Kinetics

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Solubility and Complex-Ion Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

A balloon with volume 750 cm3 is filled with O₂ at 27°C has a mass of 83.3 g. The mass of empty balloon is 82.1 g. Calculate the pressure of O₂.

Halothane (CHBrClCF₃) is one of the modern anesthetics that is nonflammable and relatively safe for patients. What is the density of halothane in grams per liter at 22°C and 805 torr?

Convert to the equivalent pressure in atmospheres, 4.32 × 10⁵ N/m².

What is the ratio of the diffusion rates of Cl₂ and O₂? Rate Cl₂ : O₂ = _______

A 4.0 L sample of N₂(g) at 760 mmHg is compressed, at constant temperature, to 3.2 atm. What is the final gas volume?

If a liter of CO₂ is compared to a liter of H₂, both at 25°C and one atmosphere pressure, then:

Three volumes of O₂ and one volume of CH₄ are placed in a sealed container. The temperature and pressure of this mixture are 120°C and 600 kPa. What is the pressure in the same container after the explosion of the mixture and after it was cooled to the initial temperature?

In the reaction Fe₂O₃ + 3 H₂ → 2 Fe + 3 H₂O, how many moles of iron can be produced using 17.4 liters of hydrogen at STP?