Question 1

In a Torricelli barometer, a pressure of one atmosphere supports a 760 mm column of mercury. If the original tube containing the mercury is replaced with a tube having twice the diameter of the original, the height of the mercury column at one atmosphere pressure is mm.

Accepted Answer

A)   760
B)   1.52 × 103 
C)   4.78 × 103 
D)   121
E)   380 A

Question 2

A sample of He gas (3.0 L) at 5.6 atm and 25 °C was combined with 4.5 L of Ne gas at 3.6 atm and 25 °C at constant temperature in a 9.0 L flask. The total pressure in the flask was atm. Assume the initial pressure in the flask was 0.00 atm.

Accepted Answer

A)   24
B)   1.0
C)   3.7
D)   2.6
E)   9.2 C

Question 3

The molar volume of a gas at STP is L.

Accepted Answer

A)   62.36
B)   14.7
C)   22.4
D)   0.08206
E)   1.00 C

Question 4

A tank containing both HF and HBr gases developed a leak. The ratio of the rate of effusion of HF to the rate of effusion of HBr is .

Accepted Answer

A)   4.04
B)   16.3
C)   0.247
D)   0.497
E)   2.01

Question 5

The pressure exerted by 1.3 mol of gas in a 13 L flask at 22 °C is kPa.

Accepted Answer

A)   250
B)   18
C)   1.0
D)   560
E)   2.4

Question 6

The van der Waals equation for real gases recognizes that .

Accepted Answer

A)   gas particles have non- zero volumes and interact with each other
B)   molar volumes of gases of different types are different
C)   the molecular attractions between particles of gas decreases the pressure exerted by the gas
D)   the non- zero volumes of gas particles effectively decrease the amount of "empty space" between them
E)   all of the above statements are true

Question 7

The molecular weight of a gas is g/mol if 3.5 g of the gas occupies 2.1 L at STP.

Accepted Answer

A)   41
B)   2.7 × 10- 2 
C)   5.5 × 103 
D)   37
E)   4.6 × 102

Question 8

At 333 K, which of the pairs of gases below would have the most nearly identical rates of effusion?

Accepted Answer

A)   N2O and NO2
B)   CO and CO2
C)   NO2 and N2O4
D)   N2 and O2
E)   CO and N2

Question 9

SO2 (5.00 g) and CO2 (5.00 g) were placed in a 750.0 mL container at 50.0 °C. The total pressure in the container was atm.

Accepted Answer

A)   0.192
B)   1.60
C)   4.02
D)   2.76
E)   6.78

Question 10

SO2 (5.00 g) and CO2 (5.00 g) are placed in a 750.0 mL container at 50.0 °C. The partial pressure of SO2 in the container was _ atm.

Accepted Answer

A)   4.02
B)   6.78
C)   2.76
D)   0.192
E)   1.60

Question 11

The volume of 0.25 mol of a gas at 72.7 kPa and 15 °C is m3.

Accepted Answer

A)   4.3 × 10- 4 
B)   1.2 × 10- 4 
C)   2.2 × 10- 1 
D)   8.1 × 10- 5 
E)   8.2 × 10- 3

Question 12

A pressure of 1.00 atm is the same as a pressure of _ of mmHg.

Accepted Answer

A)   101
B)   29.92
C)   193
D)   33.0
E)   760.0

Question 13

A fixed amount of gas at 25.0 °C occupies a volume of 10.0 L when the pressure is 629 torr. Use Charles's law to calculate the volume (L) the gas will occupy when the temperature is increased to 121 °C while maintaining the pressure at 629 torr.

Accepted Answer

A)   13.2
B)   7.56
C)   10.9
D)   2.07
E)   48.4

Question 14

The thermal decomposition of potassium chlorate can be used to produce oxygen in the laboratory.  What volume (L) of O2 gas at 25 °C and 1.00 atm pressure is produced by the decomposition of 7.5 g of KClO3 (s)?

Accepted Answer

A)   11
B)   2.2
C)   7.5
D)   4.5
E)   3.7

Question 15

The volume of hydrogen gas at 38.0 °C and 763 torr that can be produced by the reaction of 4.33 g of zinc with excess sulfuric acid is L.

Accepted Answer

A)   0.592
B)   2.84
C)   3.69 × 104
D)   1.69
E)   2.71 × 10- 4

Question 16

Which of the following statements about gases is false?

Accepted Answer

A)   Gases are highly compressible.
B)   Distances between molecules of gas are very large compared to bond distances within molecules.
C)   All gases are colorless and odorless at room temperature.
D)   Non- reacting gas mixtures are homogeneous.
E)   Gases expand spontaneously to fill the container they are placed in.

Question 17

Which one of the following gases would have the highest average molecular speed at 25 °C?

Accepted Answer

A)   SF6 
B)   CO2 
C)   O2 
D)   N2 
E)   CH4

Question 18

A 255 mL round- bottom flask is weighed and found to have a mass of 114.85 g A few milliliters of an easily vaporized liquid are added to the flask and the flask is immersed in a boiling water bath. All of the liquid vaporizes at the boiling temperature of water, filling the flask with vapor. When all of the liquid has vaporized, the flask is removed from the bath, cooled, dried, and reweighed. The new mass of the flask and the condensed vapor is 115.23g  Which of the following compounds could the liquid be? (Assume the ambient pressure is 1 atm.)

Accepted Answer

A)   C2H5OH 
B)   C4H9OH 
C)   C3H7OH 
D)   C4H10 
E)   C2H6

Question 19

A vessel contained N2, Ar, He, and Ne. The total pressure in the vessel was 987 torr. The partial pressures of nitrogen, argon, and helium were 44.0, 486, and 218 torr, respectively. The partial pressure of neon in the vessel was torr.

Accepted Answer

A)   239
B)   521
C)   19.4
D)   42.4
E)   760

Question 20

The volume of an ideal gas is zero at .

Accepted Answer

A)   - 273 °C
B)   0 °C
C)   - 45 °F
D)   - 273 K
E)   - 363 K

Exam 10: Gases

In a Torricelli barometer, a pressure of one atmosphere supports a 760 mm column of mercury. If the original tube containing the mercury is replaced with a tube having twice the diameter of the original, the height of the mercury column at one atmosphere pressure is mm.

A sample of He gas (3.0 L) at 5.6 atm and 25 °C was combined with 4.5 L of Ne gas at 3.6 atm and 25 °C at constant temperature in a 9.0 L flask. The total pressure in the flask was atm. Assume the initial pressure in the flask was 0.00 atm.

The molar volume of a gas at STP is L.

A tank containing both HF and HBr gases developed a leak. The ratio of the rate of effusion of HF to the rate of effusion of HBr is .

The pressure exerted by 1.3 mol of gas in a 13 L flask at 22 °C is kPa.

The van der Waals equation for real gases recognizes that .

The molecular weight of a gas is g/mol if 3.5 g of the gas occupies 2.1 L at STP.

At 333 K, which of the pairs of gases below would have the most nearly identical rates of effusion?

SO₂(5.00 g) and CO₂(5.00 g) were placed in a 750.0 mL container at 50.0 °C. The total pressure in the container was atm.

SO₂(5.00 g) and CO₂(5.00 g) are placed in a 750.0 mL container at 50.0 °C. The partial pressure of SO₂in the container was _ atm.

The volume of 0.25 mol of a gas at 72.7 kPa and 15 °C is m³.

A pressure of 1.00 atm is the same as a pressure of _ of mmHg.

A fixed amount of gas at 25.0 °C occupies a volume of 10.0 L when the pressure is 629 torr. Use Charles's law to calculate the volume (L) the gas will occupy when the temperature is increased to 121 °C while maintaining the pressure at 629 torr.

The thermal decomposition of potassium chlorate can be used to produce oxygen in the laboratory. What volume (L) of O₂gas at 25 °C and 1.00 atm pressure is produced by the decomposition of 7.5 g of KClO₃(s) ?

The volume of hydrogen gas at 38.0 °C and 763 torr that can be produced by the reaction of 4.33 g of zinc with excess sulfuric acid is L.

Which of the following statements about gases is false?

Which one of the following gases would have the highest average molecular speed at 25 °C?

A vessel contained N₂, Ar, He, and Ne. The total pressure in the vessel was 987 torr. The partial pressures of nitrogen, argon, and helium were 44.0, 486, and 218 torr, respectively. The partial pressure of neon in the vessel was torr.

The volume of an ideal gas is zero at .

Exam 10: Gases

In a Torricelli barometer, a pressure of one atmosphere supports a 760 mm column of mercury. If the original tube containing the mercury is replaced with a tube having twice the diameter of the original, the height of the mercury column at one atmosphere pressure is mm.

A sample of He gas (3.0 L) at 5.6 atm and 25 °C was combined with 4.5 L of Ne gas at 3.6 atm and 25 °C at constant temperature in a 9.0 L flask. The total pressure in the flask was atm. Assume the initial pressure in the flask was 0.00 atm.

The molar volume of a gas at STP is L.

A tank containing both HF and HBr gases developed a leak. The ratio of the rate of effusion of HF to the rate of effusion of HBr is .

The pressure exerted by 1.3 mol of gas in a 13 L flask at 22 °C is kPa.

The van der Waals equation for real gases recognizes that .

The molecular weight of a gas is g/mol if 3.5 g of the gas occupies 2.1 L at STP.

At 333 K, which of the pairs of gases below would have the most nearly identical rates of effusion?

SO2 (5.00 g) and CO2 (5.00 g) were placed in a 750.0 mL container at 50.0 °C. The total pressure in the container was atm.

SO2 (5.00 g) and CO2 (5.00 g) are placed in a 750.0 mL container at 50.0 °C. The partial pressure of SO2 in the container was _ atm.

The volume of 0.25 mol of a gas at 72.7 kPa and 15 °C is m3.

A pressure of 1.00 atm is the same as a pressure of _ of mmHg.

A fixed amount of gas at 25.0 °C occupies a volume of 10.0 L when the pressure is 629 torr. Use Charles's law to calculate the volume (L) the gas will occupy when the temperature is increased to 121 °C while maintaining the pressure at 629 torr.

The thermal decomposition of potassium chlorate can be used to produce oxygen in the laboratory. What volume (L) of O2 gas at 25 °C and 1.00 atm pressure is produced by the decomposition of 7.5 g of KClO3 (s) ?

The volume of hydrogen gas at 38.0 °C and 763 torr that can be produced by the reaction of 4.33 g of zinc with excess sulfuric acid is L.

Which of the following statements about gases is false?

Which one of the following gases would have the highest average molecular speed at 25 °C?

A vessel contained N2, Ar, He, and Ne. The total pressure in the vessel was 987 torr. The partial pressures of nitrogen, argon, and helium were 44.0, 486, and 218 torr, respectively. The partial pressure of neon in the vessel was torr.

The volume of an ideal gas is zero at .

SO₂(5.00 g) and CO₂(5.00 g) were placed in a 750.0 mL container at 50.0 °C. The total pressure in the container was atm.

SO₂(5.00 g) and CO₂(5.00 g) are placed in a 750.0 mL container at 50.0 °C. The partial pressure of SO₂in the container was _ atm.

The volume of 0.25 mol of a gas at 72.7 kPa and 15 °C is m³.

The thermal decomposition of potassium chlorate can be used to produce oxygen in the laboratory. What volume (L) of O₂gas at 25 °C and 1.00 atm pressure is produced by the decomposition of 7.5 g of KClO₃(s) ?

A vessel contained N₂, Ar, He, and Ne. The total pressure in the vessel was 987 torr. The partial pressures of nitrogen, argon, and helium were 44.0, 486, and 218 torr, respectively. The partial pressure of neon in the vessel was torr.