Question 1

A sample of nitrogen gas is confined to a 14.0-L container at 375 torr and 37.0°C. How many moles of nitrogen are in the container? (R = 0.08206 L • atm/K • mol, 1 atm = 760 torr)

Accepted Answer

A)  0.272 mol 
B)  2.27 mol 
C)  3.69 mol 
D)  206 mol 
E)  227 mol 
A)  0.272 mol 
B)  2.27 mol 
C)  3.69 mol 
D)  206 mol 
E)  227 mol

Question 2

What mass of KClO3 must be decomposed to produce 126 L of oxygen gas at 133°C and 0.880 atm? (The other reaction product is solid KCl.) (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  24.6 g 
B)  70.8 g 
C)  272 g 
D)  408 g 
E)  612 g 
A)  24.6 g 
B)  70.8 g 
C)  272 g 
D)  408 g 
E)  612 g

Question 3

A 2.50-L flask contains a mixture of methane (CH4) and propane (C3H8) at a pressure of 1.45 atm and 20°C. When this gas mixture is then burned in excess oxygen, 8.60 g of carbon dioxide is formed. (The other product is water.) What is the mole fraction of methane in the original gas mixture?

Accepted Answer

A)  0.34 
B)  1.00 
C)  0.66 
D)  0.85 
E)  0.15 
A)  0.34 
B)  1.00 
C)  0.66 
D)  0.85 
E)  0.15

Question 4

A 7.75-L flask contains 0.482 g of hydrogen gas and 4.98 g of oxygen gas at 65°C. What is the partial pressure of oxygen in the flask?

Accepted Answer

A)  0.557 atm 
B)  0.043 atm 
C)  1.11 atm 
D)  33.5 atm 
E)  67 atm 
A)  0.557 atm 
B)  0.043 atm 
C)  1.11 atm 
D)  33.5 atm 
E)  67 atm

Question 5

A flask containing neon gas is connected to an open-ended mercury manometer. The open end is exposed to the atmosphere, where the prevailing pressure is 745 torr. The mercury level in the open arm is 5.0 cm below that in the arm connected to the flask of neon. What is the neon pressure, in torr?

Accepted Answer

A)  -50. torr 
B)  50. torr 
C)  695 torr 
D)  745 torr 
E)  795 torr 
A)  -50. torr 
B)  50. torr 
C)  695 torr 
D)  745 torr 
E)  795 torr

Question 6

A sample of carbon dioxide gas at 125°C and 248 torr occupies a volume of 275 L. What will the gas pressure be if the volume is increased to 321 L at 125°C?

Accepted Answer

A)  212 torr 
B)  289 torr 
C)  356 torr 
D)  441 torr 
E)  359 torr 
A)  212 torr 
B)  289 torr 
C)  356 torr 
D)  441 torr 
E)  359 torr

Question 7

An aerosol can with a volume of 0.50 L has a bursting point of 2.6 atm. If the can contains 1.0 g CO2 and is heated to 400°C, will it burst?

Accepted Answer

Question 8

What is the density of SF6(g) at 27°C and 0.500 atm pressure? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  3.38 × 10-3 g/L 
B)  2.97 g/L 
C)  22.4 g/L 
D)  32.9 g/L 
E)  3.38 kg/L 
A)  3.38 × 10-3 g/L 
B)  2.97 g/L 
C)  22.4 g/L 
D)  32.9 g/L 
E)  3.38 kg/L

Question 9

How many molecules of N2 gas are present in a 2.5-L flask at 50°C and 650 mmHg? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg, 1 mole = 6.022 × 1023 molecules)

Accepted Answer

A)  2.1 × 10-23 molecules 
B)  4.9 × 1022 molecules 
C)  3.1 × 1023 molecules 
D)  3.6 × 1025 molecules 
E)  0.081 molecules 
A)  2.1 × 10-23 molecules 
B)  4.9 × 1022 molecules 
C)  3.1 × 1023 molecules 
D)  3.6 × 1025 molecules 
E)  0.081 molecules

Question 10

________ is the formula to determine the molar mass of a compound using the ideal gas law.

Accepted Answer

The answer of ________ is the formula to determine the...

Question 11

What is the formula which describes the relationship between the pressure, volume, temperature, and moles?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 12

What are the conditions of STP?

Accepted Answer

A)  0 K and 1 atm 
B)  273.15 K and 760 torr 
C)  0°C and 760 atm 
D)  273.15°C and 760 torr 
E)  0°C and 1 torr 
A)  0 K and 1 atm 
B)  273.15 K and 760 torr 
C)  0°C and 760 atm 
D)  273.15°C and 760 torr 
E)  0°C and 1 torr

Question 13

A spacecraft is filled with 0.500 atm of N2 and 0.500 atm of O2. Suppose an object strikes this spacecraft and puts a very small hole in its side. Under these circumstances,

Accepted Answer

A)  O2 is lost from the craft 6.9% faster than N2 is lost. 
B)  O2 is lost from the craft 14% faster than N2 is lost. 
C)  N2 is lost from the craft 6.9% faster than O2 is lost. 
D)  N2 is lost from the craft 14% faster than O2 is lost. 
E)  N2 and O2 are lost from the craft at the same rate. 
A)  O2 is lost from the craft 6.9% faster than N2 is lost. 
B)  O2 is lost from the craft 14% faster than N2 is lost. 
C)  N2 is lost from the craft 6.9% faster than O2 is lost. 
D)  N2 is lost from the craft 14% faster than O2 is lost. 
E)  N2 and O2 are lost from the craft at the same rate.

Question 14

The catalytic decomposition of hydrogen peroxide yields oxygen gas and water. In an experiment, decomposition of hydrogen peroxide yielded 75.3 mL of gas collected over water at 25°C and 742 torr. What mass of oxygen gas was collected? (Pwater = 24 torr at 25°C, R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  0.00291 g 
B)  0.0931 g 
C)  0.0962 g 
D)  0.0993 g 
E)  0.962 g 
A)  0.00291 g 
B)  0.0931 g 
C)  0.0962 g 
D)  0.0993 g 
E)  0.962 g

Question 15

A flask with a volume of 3.16 L contains 9.33 g of an unknown gas at 32.0°C and 1.00 atm. What is the molar mass of the gas? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  7.76 g/mol 
B)  66.1 g/mol 
C)  73.9 g/mol 
D)  81.4 g/mol 
E)  144 g/mol 
A)  7.76 g/mol 
B)  66.1 g/mol 
C)  73.9 g/mol 
D)  81.4 g/mol 
E)  144 g/mol

Question 16

A(n) ________ is an instrument used to measure the atmospheric pressure.

Accepted Answer

The answer of A(n) ________ is an instrument used to...

Question 17

_______ ________ states that the volume of a fixed amount of gas maintained at constant pressure is directly proportional to the absolute temperature of a gas.

Accepted Answer

The answer of _______ ________ states that the volume of...

Question 18

How many grams of carbon dioxide are contained in 550 mL of this gas at STP?

Accepted Answer

A)  0.0245 g 
B)  0.0280 g 
C)  1080 g 
D)  0.560 g 
E)  1.1 g 
A)  0.0245 g 
B)  0.0280 g 
C)  1080 g 
D)  0.560 g 
E)  1.1 g

Question 19

A sample of gas occupies 24.5 L at a pressure of 1.57 atm. What is the pressure if the volume is increased to 48.3 L at constant temperature?

Accepted Answer

A)  0.796 atm 
B)  1.26 atm 
C)  3.10 atm 
D)  5.38 × 10-4 atm 
E)  1.86 × 103 atm 
A)  0.796 atm 
B)  1.26 atm 
C)  3.10 atm 
D)  5.38 × 10-4 atm 
E)  1.86 × 103 atm

Question 20

Gases form heterogeneous mixtures or solutions with one another.

Accepted Answer

A) True 
 B)False

Exam 10: Gases

A sample of nitrogen gas is confined to a 14.0-L container at 375 torr and 37.0°C. How many moles of nitrogen are in the container? (R = 0.08206 L • atm/K • mol, 1 atm = 760 torr)

What mass of KClO3 must be decomposed to produce 126 L of oxygen gas at 133°C and 0.880 atm? (The other reaction product is solid KCl.) (R = 0.08206 L • atm/K • mol)

A 2.50-L flask contains a mixture of methane (CH4) and propane (C3H8) at a pressure of 1.45 atm and 20°C. When this gas mixture is then burned in excess oxygen, 8.60 g of carbon dioxide is formed. (The other product is water.) What is the mole fraction of methane in the original gas mixture?

A 7.75-L flask contains 0.482 g of hydrogen gas and 4.98 g of oxygen gas at 65°C. What is the partial pressure of oxygen in the flask?

A flask containing neon gas is connected to an open-ended mercury manometer. The open end is exposed to the atmosphere, where the prevailing pressure is 745 torr. The mercury level in the open arm is 5.0 cm below that in the arm connected to the flask of neon. What is the neon pressure, in torr?

A sample of carbon dioxide gas at 125°C and 248 torr occupies a volume of 275 L. What will the gas pressure be if the volume is increased to 321 L at 125°C?

An aerosol can with a volume of 0.50 L has a bursting point of 2.6 atm. If the can contains 1.0 g CO2 and is heated to 400°C, will it burst?

What is the density of SF6(g) at 27°C and 0.500 atm pressure? (R = 0.08206 L • atm/K • mol)

How many molecules of N2 gas are present in a 2.5-L flask at 50°C and 650 mmHg? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg, 1 mole = 6.022 × 1023 molecules)

________ is the formula to determine the molar mass of a compound using the ideal gas law.

What is the formula which describes the relationship between the pressure, volume, temperature, and moles?

What are the conditions of STP?

A spacecraft is filled with 0.500 atm of N2 and 0.500 atm of O2. Suppose an object strikes this spacecraft and puts a very small hole in its side. Under these circumstances,

The catalytic decomposition of hydrogen peroxide yields oxygen gas and water. In an experiment, decomposition of hydrogen peroxide yielded 75.3 mL of gas collected over water at 25°C and 742 torr. What mass of oxygen gas was collected? (Pwater = 24 torr at 25°C, R = 0.08206 L • atm/K • mol)

A flask with a volume of 3.16 L contains 9.33 g of an unknown gas at 32.0°C and 1.00 atm. What is the molar mass of the gas? (R = 0.08206 L • atm/K • mol)

A(n) ________ is an instrument used to measure the atmospheric pressure.

_______ ________ states that the volume of a fixed amount of gas maintained at constant pressure is directly proportional to the absolute temperature of a gas.

How many grams of carbon dioxide are contained in 550 mL of this gas at STP?

A sample of gas occupies 24.5 L at a pressure of 1.57 atm. What is the pressure if the volume is increased to 48.3 L at constant temperature?

Gases form heterogeneous mixtures or solutions with one another.

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

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Coordination Chemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

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What mass of KClO₃ must be decomposed to produce 126 L of oxygen gas at 133°C and 0.880 atm? (The other reaction product is solid KCl.) (R = 0.08206 L • atm/K • mol)

A 2.50-L flask contains a mixture of methane (CH₄) and propane (C₃H₈) at a pressure of 1.45 atm and 20°C. When this gas mixture is then burned in excess oxygen, 8.60 g of carbon dioxide is formed. (The other product is water.) What is the mole fraction of methane in the original gas mixture?

An aerosol can with a volume of 0.50 L has a bursting point of 2.6 atm. If the can contains 1.0 g CO₂ and is heated to 400°C, will it burst?

What is the density of SF₆(g) at 27°C and 0.500 atm pressure? (R = 0.08206 L • atm/K • mol)

How many molecules of N₂ gas are present in a 2.5-L flask at 50°C and 650 mmHg? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg, 1 mole = 6.022 × 10²³ molecules)

A spacecraft is filled with 0.500 atm of N₂ and 0.500 atm of O₂. Suppose an object strikes this spacecraft and puts a very small hole in its side. Under these circumstances,

The catalytic decomposition of hydrogen peroxide yields oxygen gas and water. In an experiment, decomposition of hydrogen peroxide yielded 75.3 mL of gas collected over water at 25°C and 742 torr. What mass of oxygen gas was collected? (P_water = 24 torr at 25°C, R = 0.08206 L • atm/K • mol)

_ __ states that the volume of a fixed amount of gas maintained at constant pressure is directly proportional to the absolute temperature of a gas.