Question 1

The rate of diffusion of a gas is inversely proportional to its molar mass.

Accepted Answer

A) True 
 B)False

Question 2

Gases are sold in large cylinders for laboratory use. What pressure is exerted by 2.500 kg of oxygen gas (O2) stored at 22°C in a 40.0-L cylinder? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  3.55 atm 
B)  1.51 ×103 atm 
C)  47.3 atm 
D)  7.56 × 104 atm 
E)  10.2 atm 
A)  3.55 atm 
B)  1.51 ×103 atm 
C)  47.3 atm 
D)  7.56 × 104 atm 
E)  10.2 atm

Question 3

What is the initial pressure of a gas having an initial temperature of 905 K, an initial volume of 14.3 L, a final pressure of 0.83 atm, a final temperature of 154 K and a final volume of 2.7 L?

Accepted Answer

A)  26 atm 
B)  0.27 atm 
C)  0.75 atm 
D)  1.3 atm 
E)  0. 92 atm 
A)  26 atm 
B)  0.27 atm 
C)  0.75 atm 
D)  1.3 atm 
E)  0. 92 atm

Question 4

A sample of a gas occupies 1.40 L at 25°C and 760 mmHg. What volume will it occupy at the same temperature and 380 mmHg?

Accepted Answer

A)  2.8 L 
B)  2.10 L 
C)  1.40 L 
D)  1.05 L 
E)  0.700 L 
A)  2.8 L 
B)  2.10 L 
C)  1.40 L 
D)  1.05 L 
E)  0.700 L

Question 5

Give five examples of compounds that exist as gases at room temperature and atmospheric pressure.

Accepted Answer

(Answers will vary.)

Question 6

1.000 atm of oxygen gas, placed in a container having a pinhole opening in its side, leaks from the container 2.14 times faster than does 1.000 atm of an unknown gas placed in this same apparatus. Which of the following species could be the unknown gas?

Accepted Answer

A)  Cl2 
B)  SF6 
C)  Kr 
D)  UF6 
E)  Xe 
A)  Cl2 
B)  SF6 
C)  Kr 
D)  UF6 
E)  Xe

Question 7

The Kelvin temperature scale is useful when comparing

Accepted Answer

A)  various gas samples at different densities. 
B)  volume of a gas sample with temperature at constant pressure. 
C)  pressure of gas samples at different volumes and constant temperature. 
D)  various liquids at constant pressure. 
A)  various gas samples at different densities. 
B)  volume of a gas sample with temperature at constant pressure. 
C)  pressure of gas samples at different volumes and constant temperature. 
D)  various liquids at constant pressure.

Question 8

A compound composed of carbon, hydrogen, and chlorine effuses through a pinhole 0.411 times as fast as neon. What is the molecular formula of the compound?

Accepted Answer

A)  CHCl3 
B)  CH2Cl2 
C)  C2H2Cl2 
D)  C2H3Cl 
E)  CCl4 
A)  CHCl3 
B)  CH2Cl2 
C)  C2H2Cl2 
D)  C2H3Cl 
E)  CCl4

Question 9

"The pressure of an ideal gas is inversely proportional to its volume at constant temperature and number of moles" is a statement of ________ law.

Accepted Answer

A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's 
A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's

Question 10

Consider the following reaction. H2(g) + I2(s) → 2 HI(g)
If the cylinder with a movable piston below contains 1 mol H2(g) and 1 mol I2(s), which represents the cylinder after the reaction is complete?

Accepted Answer

A)    
B)    
C)    
D)    
E)  None of these choices. 
A)    
B)    
C)    
D)    
E)  None of these choices.

Question 11

The air pressure in a volleyball is 75 psi. What is this pressure in torr? (1 atm = 14.7 psi = 101,325 Pa = 760 torr)?

Accepted Answer

A)  520 torr 
B)  562 torr 
C)  3900 torr 
D)  7600 torr 
E)  75,000 torr 
A)  520 torr 
B)  562 torr 
C)  3900 torr 
D)  7600 torr 
E)  75,000 torr

Question 12

What is the pressure in atmospheres exerted by a column of mercury that is 100. m high? (density of mercury = 13.5951 g/cm3, gravitational constant = 9.80665 m/s2, 1 atm = 101,325 Pa = 760 torr = 760 mmHg)

Accepted Answer

A)  1.4 × 1010 atm 
B)  0.013 atm 
C)  0.73 atm 
D)  1.37 atm 
E)  132 atm 
A)  1.4 × 1010 atm 
B)  0.013 atm 
C)  0.73 atm 
D)  1.37 atm 
E)  132 atm

Question 13

What is the volume of NH3 produced in the following reaction when 3.0 L of N2 reacts with 4.0 L of H2 ? N2(g) + 3H2(g) → 2NH3(g)

Accepted Answer

A)  1.5 L 
B)  2.7 L 
C)  6.0 L 
D)  7.5 L 
E)  12 L 
A)  1.5 L 
B)  2.7 L 
C)  6.0 L 
D)  7.5 L 
E)  12 L

Question 14

A(n) ________ is a device used to measure the pressure of gases other than the atmosphere.

Accepted Answer

The answer of A(n) ________ is a device used to...

Question 15

A 0.271-g sample of an unknown vapor occupies 294 mL at 140°C and 847 mmHg. The empirical formula of the compound is CH2. What is the molecular formula of the compound? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  CH2 
B)  C2H4 
C)  C3H6 
D)  C4H8 
E)  C6H12 
A)  CH2 
B)  C2H4 
C)  C3H6 
D)  C4H8 
E)  C6H12

Question 16

A sample of nitrogen gas has a volume of 32.4 L at 20°C. The gas is heated to 220ºC at constant pressure. What is the final volume of the nitrogen gas?

Accepted Answer

A)  2.94 L 
B)  19.3 L 
C)  32.4 L 
D)  54.5 L 
E)  356 L 
A)  2.94 L 
B)  19.3 L 
C)  32.4 L 
D)  54.5 L 
E)  356 L

Question 17

A gas evolved during the fermentation of sugar was collected at 22.5°C and 702 mmHg. After purification its volume was found to be 25.0 L. How many moles of gas were collected? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg)

Accepted Answer

A)  0.952 mol 
B)  1.05 mol 
C)  12.5 mol 
D)  22.4 mol 
E)  724 mol 
A)  0.952 mol 
B)  1.05 mol 
C)  12.5 mol 
D)  22.4 mol 
E)  724 mol

Question 18

In the van der Waals equation, the constant b is a constant that is part of a correction factor for ________.

Accepted Answer

A)  the volume of the gas 
B)  the temperature of the gas 
C)  the pressure of the gas 
D)  the ideal gas constant 
A)  the volume of the gas 
B)  the temperature of the gas 
C)  the pressure of the gas 
D)  the ideal gas constant

Question 19

The mole fraction of oxygen molecules in dry air is 0.2095. What volume of dry air at 1.00 atm and 25°C is required for burning completely 1.00 L of octane (C8H18, density = 0.7025 g/mL), yielding carbon dioxide and water? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  394 L 
B)  1880 L 
C)  8220 L 
D)  8970 L 
E)  17,900 L 
A)  394 L 
B)  1880 L 
C)  8220 L 
D)  8970 L 
E)  17,900 L

Question 20

What is the standard pressure used for STP conditions?

Accepted Answer

1 atm or 7

Exam 10: Gases

The rate of diffusion of a gas is inversely proportional to its molar mass.

Gases are sold in large cylinders for laboratory use. What pressure is exerted by 2.500 kg of oxygen gas (O2) stored at 22°C in a 40.0-L cylinder? (R = 0.08206 L • atm/K • mol)

What is the initial pressure of a gas having an initial temperature of 905 K, an initial volume of 14.3 L, a final pressure of 0.83 atm, a final temperature of 154 K and a final volume of 2.7 L?

A sample of a gas occupies 1.40 L at 25°C and 760 mmHg. What volume will it occupy at the same temperature and 380 mmHg?

Give five examples of compounds that exist as gases at room temperature and atmospheric pressure.

1.000 atm of oxygen gas, placed in a container having a pinhole opening in its side, leaks from the container 2.14 times faster than does 1.000 atm of an unknown gas placed in this same apparatus. Which of the following species could be the unknown gas?

The Kelvin temperature scale is useful when comparing

A compound composed of carbon, hydrogen, and chlorine effuses through a pinhole 0.411 times as fast as neon. What is the molecular formula of the compound?

"The pressure of an ideal gas is inversely proportional to its volume at constant temperature and number of moles" is a statement of ________ law.

Consider the following reaction. H2(g) + I2(s) → 2 HI(g) If the cylinder with a movable piston below contains 1 mol H2(g) and 1 mol I2(s), which represents the cylinder after the reaction is complete?

The air pressure in a volleyball is 75 psi. What is this pressure in torr? (1 atm = 14.7 psi = 101,325 Pa = 760 torr)?

What is the pressure in atmospheres exerted by a column of mercury that is 100. m high? (density of mercury = 13.5951 g/cm3, gravitational constant = 9.80665 m/s2, 1 atm = 101,325 Pa = 760 torr = 760 mmHg)

What is the volume of NH3 produced in the following reaction when 3.0 L of N2 reacts with 4.0 L of H2 ? N2(g) + 3H2(g) → 2NH3(g)

A(n) ________ is a device used to measure the pressure of gases other than the atmosphere.

A 0.271-g sample of an unknown vapor occupies 294 mL at 140°C and 847 mmHg. The empirical formula of the compound is CH2. What is the molecular formula of the compound? (R = 0.08206 L • atm/K • mol)

A sample of nitrogen gas has a volume of 32.4 L at 20°C. The gas is heated to 220ºC at constant pressure. What is the final volume of the nitrogen gas?

A gas evolved during the fermentation of sugar was collected at 22.5°C and 702 mmHg. After purification its volume was found to be 25.0 L. How many moles of gas were collected? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg)

In the van der Waals equation, the constant b is a constant that is part of a correction factor for ________.

The mole fraction of oxygen molecules in dry air is 0.2095. What volume of dry air at 1.00 atm and 25°C is required for burning completely 1.00 L of octane (C8H18, density = 0.7025 g/mL), yielding carbon dioxide and water? (R = 0.08206 L • atm/K • mol)

What is the standard pressure used for STP conditions?

Chemistry: the Central Science

Atoms, Molecules, and Ions

Stoichiometry: Ratios of Combination

Reactions in Aqueous Solutions

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Electron Configuration and the Periodic Table

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Molecular Geometry and Bonding Theories

Intermolecular Forces and the Physical Properties of Liquids and Solids

Modern Materials

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy, Free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Environmental Chemistry

Coordination Chemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Organic Chemistry

Filters

Gases are sold in large cylinders for laboratory use. What pressure is exerted by 2.500 kg of oxygen gas (O₂) stored at 22°C in a 40.0-L cylinder? (R = 0.08206 L • atm/K • mol)

Consider the following reaction. H₂(g) + I₂(s) → 2 HI(g) If the cylinder with a movable piston below contains 1 mol H₂(g) and 1 mol I₂(s), which represents the cylinder after the reaction is complete?

What is the pressure in atmospheres exerted by a column of mercury that is 100. m high? (density of mercury = 13.5951 g/cm³, gravitational constant = 9.80665 m/s², 1 atm = 101,325 Pa = 760 torr = 760 mmHg)

What is the volume of NH₃ produced in the following reaction when 3.0 L of N₂ reacts with 4.0 L of H₂ ? N₂(g) + 3H₂(g) → 2NH₃(g)

A 0.271-g sample of an unknown vapor occupies 294 mL at 140°C and 847 mmHg. The empirical formula of the compound is CH₂. What is the molecular formula of the compound? (R = 0.08206 L • atm/K • mol)

The mole fraction of oxygen molecules in dry air is 0.2095. What volume of dry air at 1.00 atm and 25°C is required for burning completely 1.00 L of octane (C₈H₁₈, density = 0.7025 g/mL), yielding carbon dioxide and water? (R = 0.08206 L • atm/K • mol)