Deck 5: Gases

Question 1

If the pressure of a gas sample is tripled and the absolute temperature is quadrupled, by what factor will the volume of the sample change

A) 12
B) 4/3
C) 3/4
D) 1/3
E) 4

Answer 1

4/3

Question 2

A small bubble rises from the bottom of a lake, where the temperature and pressure are 4 ^$\circ$ C and 3.0 atm, to the water's surface, where the temperature is 25 ^$\circ$ C and the pressure is 0.95 atm. Calculate the final volume of the bubble if its initial volume was 2.1 mL.

A) 0.72 mL
B) 6.2 mL
C) 7.1 mL
D) 22.4 mL
E) 41.4 mL

Answer 2

7.1 mL

Question 3

Which of the following statements is consistent with Boyle's Law concerning an ideal gas

A) At constant temperature and moles, a plot of volume versus pressure is linear.
B) At constant pressure and volume, a plot of temperature versus moles is linear.
C) At constant pressure and moles, a plot of temperature versus volume is linear.
D) At constant temperature and moles, a plot of pressure versus the inverse of volume is linear.
E) At constant temperature and pressure, a plot of moles versus volume is linear.

Answer 3

At constant temperature and moles, a plot of pressure versus the inverse of volume is linear.

Question 4

Which of the following describes Dalton's Law

A) The pressure of a gas is proportional to its volume.
B) The total pressure of a gas mixture is the sum of the partial pressures of each gas in the mixture.
C) The temperature of a gas is proportional to its volume.
D) Only one variable can be changed from an initial state to a final state for a gas.

Question 5

The gas pressure in an aerosol can is 1.8 atm at 25 ^$\circ$ C. If the gas is an ideal gas, what pressure would develop in the can if it were heated to 475 ^$\circ$ C

A) 0.095 atm
B) 0.72 atm
C) 3.3 atm
D) 4.5 atm
E) 34 atm

Question 6

Which of these properties is/are characteristic(s) of gases

A) High compressibility
B) Relatively large distances between molecules
C) Formation of homogeneous mixtures regardless of the nature of gases
D) A and B.
E) A, B, and C.

Question 7

If the pressure of a gas sample is quadrupled and the absolute temperature is doubled, by what factor does the volume of the sample change

A) 8
B) 2
C) 1/2
D) 1/4
E) 1/8

Question 8

A 45 mL sample of nitrogen gas is cooled from 135ºC to 15 ^$\circ$ C in a container that can contract or expand at constant pressure. What is the new volume of the nitrogen gas

A) 64 mL
B) 5.0 mL
C) 410 mL
D) 32 mL
E) 41 mL

Question 9

The pressure of a gas sample was measured to be 654 mmHg. What is the pressure in kPa (1 atm = 1.01325 * 10⁵ Pa)

A) 87.2 kPa
B) 8.72 * 10⁴ kPa
C) 118 kPa
D) 8.72 * 10⁷ kPa
E) 6.63 * 10⁴ kPa

Question 10

A sample of helium gas occupies 355mL at 23 ^$\circ$ C. If the container the He is in is expanded to 1.50 L at constant pressure, what is the final temperature for the He at this new volume

A) 1,250 ^$\circ$ C
B) 978 ^$\circ$ C
C) 70.1 ^$\circ$ C
D) 80.0 ^$\circ$ C
E) 1,520 ^$\circ$ C

Question 11

What is the pressure of the sample of gas trapped in the open-tube mercury manometer shown below if atmospheric pressure is 736 mmHg and h = 9.2 cm

A) 92 mmHg
B) 644 mmHg
C) 736 mmHg
D) 828 mmHg

Question 12

At constant temperature, the volume of the container that a sample of nitrogen gas is in is doubled. As a result the pressure of the nitrogen gas is halved. The amount of nitrogen gas is unchanged in this process. This is an example of:

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

Question 13

A sample of a gas occupies 1.40 * 10³ mL at 25 ^$\circ$ C and 760 mmHg. What volume will it occupy at the same temperature and 380 mmHg

A) 2,800 mL
B) 2,100 mL
C) 1,400 mL
D) 1,050 mL
E) 700 mL

Question 14

A sample of pure oxygen gas has a pressure of 795 torr. What is the pressure of the oxygen in units of atmospheres

A) 0.795 atm
B) 1.05 atm
C) 0.604 atm
D) 0.760 atm
E) 1.01 atm

Question 15

At constant temperature and volume, a sample of oxygen gas is added to a sample of nitrogen gas. The pressure of the mixture is found by adding the pressures of the two individual gases. This is an example of:

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

Question 16

A pressure that will support a column of Hg to a height of 256 mm would support a column of water to what height The density of mercury is 13.6 g/cm³; the density of water is 1.00 g/cm³.

A) 1.00 * 10² ft
B) 18.8 mm
C) 33.8 ft
D) 76.0 cm
E) 348 cm

Question 17

A sample of oxygen gas has a volume of 545 mL at 35 ^$\circ$ C. The gas is heated to 151ºC at constant pressure in a container that can contract or expand. What is the final volume of the oxygen gas

A) 750. mL
B) 396 mL
C) 417 mL
D) 267 mL
E) 126 mL

Question 18

A sample of pure nitrogen has a temperature of 15 ^$\circ$ C. What is the temperature of the nitrogen in units of Kelvin

A) 300 K
B) 290 K
C) 288 K
D) 288.2 K
E) 288.15 K

Question 19

What will happen to the height (h) of the mercury column in the manometer shown below if the stopcock is opened, given that the atmospheric pressure is 755 mmHg

A) h will decrease
B) h will not change
C) h will increase
D) not enough information given to answer the question

Question 20

What will happen to the height (h) of the column of mercury in the manometer shown below if the stopcock is opened

A) h will decrease
B) h will not change
C) h will increase
D) not enough information given to answer the question

Question 21

0.820 mole of hydrogen gas has a volume of 2.00 L at a certain temperature and pressure. What is the volume of 0.125 mol of this gas at the same temperature and pressure

A) 0.0512 L
B) 0.250 L
C) 0.305 L
D) 4.01 L
E) 19.5 L

Question 22

Calculate the density, in g/L, of SF₆ gas at 27 ^$\circ$ C and 0.500 atm pressure.

A) 3.38 * 10^-3 g/L
B) 2.96 g/L
C) 22.4 g/L
D) 32.9 g/L
E) 3.38 kg/L

Question 23

Calculate the grams of SO₂ gas present at STP in a 5.9 L container.

A) 0.24 g
B) 0.26 g
C) 15 g
D) 17 g
E) 64 g

Question 24

Calculate the number of moles of gas contained in a 10.0 L tank at 22 ^$\circ$ C and 105 atm. (R = 0.08206 L.atm/K.mol)

A) 1.71 * 10^-3 mol
B) 0.0231 mol
C) 1.03 mol
D) 43.4 mol
E) 582 mol

Question 25

Gases are sold in large cylinders for laboratory use. What pressure, in atmospheres, will be exerted by 2,500 g of oxygen gas (O₂) when stored at 22 ^$\circ$ C in a 40.0 L cylinder

A) 3.6 atm
B) 10. atm
C) 47 atm
D) 1,500 atm
E) 7.6 * 10⁴ atm

Question 26

A 250 mL flask contains 3.4 g of neon gas at 45 ^$\circ$ C. Calculate the pressure of the neon gas inside the flask.

A) 0.050 atm
B) 0.46 atm
C) 18 atm
D) 38 atm
E) 3.5 x 10² atm

Question 27

Calculate the volume occupied by 25.2 g of CO₂ at 0.84 atm and 25 ^$\circ$ C. R = 0.08206 L.atm/K.mol.

A) 0.060 L
B) 1.34 L
C) 16.7 L
D) 24.2 L
E) 734 L

Question 28

At what temperature will a sample of nitrogen gas with a volume of 328 mL at 15 ^$\circ$ C and 748 mmHg occupy a volume of 0.898 L at a pressure of 642 mm Hg Assume the amount of the nitrogen gas does not change.

A) 676 ^$\circ$ C
B) 404 ^$\circ$ C
C) 396 ^$\circ$ C
D) 274 ^$\circ$ C
E) 123 ^$\circ$ C

Question 29

Calculate the density, in g/L, of chlorine (Cl₂) gas at STP.

A) 2.13 * 10^-2 g/L
B) 1.58 g/L
C) 3.16 g/L
D) 46.9 g/L
E) 0.316 kg/L

Question 30

How many atoms of Ar gas are present in a 340 mL container at 55 ^$\circ$ C and 720 mmHg

A) 0.012 Ar atoms
B) 7.2 x 10²¹ Ar atoms
C) 4.3 x 10²² Ar atoms
D) 2.9 x 10²³ Ar atoms
E) 1.7 x 10²⁴ Ar atoms

Question 31

How many atoms of He gas are present in a 450 mL container at 35 ^$\circ$ C and 740 mmHg

A) 0.017 He atoms
B) 0.068 He atoms
C) 1.2 x 10⁵ He atoms
D) 1.0 x 10²² He atoms
E) 7.9 x 10²⁴ He atoms

Question 32

Calculate the mass, in grams, of 2.74 L of CO gas measured at 33 ^$\circ$ C and 945 mmHg.

A) 0.263 g
B) 2.46 g
C) 3.80 g
D) 35.2 g
E) 206 g

Question 33

The temperature of a sample of argon gas in a 365 mL container at 740. mmHg and 25 ^$\circ$ C is lowered to 12 ^$\circ$ C. Assuming the volume of the container and the amount of gas is unchanged, calculate the new pressure of the argon.

A) 0.468 atm
B) 0.931 atm
C) 1.02 atm
D) 1.54 atm
E) 2.03 atm

Question 34

At what temperature will a sample of oxygen gas with a volume of 0.110 L at 12 ^$\circ$ C and 822 mmHg occupy a volume of 345 mL at a pressure of 578 mm Hg Assume the amount of the oxygen gas does not change.

A) 129 ^$\circ$ C
B) 355 ^$\circ$ C
C) 402 ^$\circ$ C
D) 629 ^$\circ$ C
E) 903 ^$\circ$ C

Question 35

Calculate the volume occupied by 56.5 g of argon gas at STP.

A) 22.4 L
B) 31.7 L
C) 34.6 L
D) 1,270 L
E) 1,380 L

Question 36

Calculate the density, in g/L, of N₂ gas at 35 ^$\circ$ C and 0.98 atm pressure.

A) 0.039 g/L
B) 0.34 g/L
C) 0.54 g/L
D) 1.1 g/L
E) 9.6 g/L

Question 37

A gas evolved during the fermentation of sugar was collected. After purification its volume was found to be 25.0 L at 22.5 ^$\circ$ C and 702 mmHg. How many moles of gas were collected

A) 0.95 mol
B) 1.05 mol
C) 12.5 mol
D) 22.4 mol
E) 724 mol

Question 38

Calculate the volume occupied by 35.2 g of methane gas (CH₄) at 25 ^$\circ$ C and 1.0 atm. R = 0.08206 L.atm/K.mol.

A) 0.0186 L
B) 4.5 L
C) 11.2 L
D) 49.2 L
E) 53.7 L

Question 39

Calculate the density of CO₂(g) at 120 ^$\circ$ C and 790 mmHg pressure.

A) 0.032 g/L
B) 1.4 g/L
C) 1.8 g/L
D) 3.4 g/L
E) 8.0 g/L

Question 40

Calculate the density of Br₂(g) at 59.0 ^$\circ$ C and 1.00 atm pressure.

A) 3.45 g/L
B) 5.83 g/L
C) 22.4 g/L
D) 27.2 g/L
E) 769 g/L

Question 41

Determine the molar mass of Freon-11 gas if a sample weighing 0.597 g occupies 100. cm³ at 95 ^$\circ$ C, and 1,000. mmHg.

A) 0.19 g/mol
B) 35.3 g/mol
C) 70.9 g/mol
D) 137 g/mol
E) 384 g/mol

Question 42

What volume of sulfur dioxide gas at 45 ^$\circ$ C and 723 mmHg will react completely with 0.870 L of oxygen gas at constant temperature and pressure?
2 SO₂(g) + O₂(g) $\rarr$ 2SO₃(g)

A) 0.0317 L
B) 0.0634 L
C) 0.870 L
D) 1.74 L
E) 3.48 L

Question 43

Determine the molar mass of chloroform gas if a sample weighing 0.389 g is collected in a flask with a volume of 102 cm³ at 97 ^$\circ$ C. The pressure of the chloroform is 728 mmHg.

A) 8.28 * 10^-3 g/mol
B) 31.6 g/mol
C) 112 g/mol
D) 121g/mol
E) 187g/mol

Question 44

Air contains 78% N₂, 21% O₂, and 1% Ar, by volume. What is the density of air at 1,000. torr and -10 ^$\circ$ C

A) 0.56 g/L
B) 1.0 g/L
C) 1.3 g/L
D) 1.8 g/L
E) 6.1 g/L

Question 45

What is the molar mass of Freon-11 gas if its density is 6.13 g/L at STP

A) 0.274 g/mol
B) 3.64 g/mol
C) 78.2 g/mol
D) 137 g/mol
E) 365 g/mol

Question 46

1.018 g of Freon-113 gas is trapped in a 145 mL container at 760. mmHg and 50.0 ^$\circ$ C. What is the molar mass of Freon-113

A) 21.7 g/mol
B) 28.8 g/mol
C) 46.1 g/mol
D) 186 g/mol
E) 245 g/mol

Question 47

A 0.271 g sample of an unknown vapor occupies 294 mL at 140. ^$\circ$ C and 847 mmHg. The empirical formula of the compound is CH₂. What is the molecular formula of the compound

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

Question 48

A 707 mg sample of a gas containing only carbon and oxygen occupies a volume of 452 mL at 63 ^$\circ$ C and 745 mmHg. Identify the gas in the sample. (R = 0.08206 L*atm/K*mol)

A) CO
B) CO₂
C) CO₃^2-
D) C₂O
E) C₂O₂

Question 49

A sample of hydrogen gas was collected over water at 21 ^$\circ$ C and 685 mmHg. The volume of the container was 7.80 L. Calculate the mass of H₂(g) collected. (Vapor pressure of water = 18.6 mmHg at 21 ^$\circ$ C.)

A) 0.283 g
B) 0.572 g
C) 0.589 g
D) 7.14 g
E) 435 g

Question 50

Gas A and gas B are combined in a flask at initial pressures of 1.0 atm each. The flask is sealed and over time they react to completion to give gas C according to the following chemical equation: 2A(g) + B(g) $\rarr$ C(g)
Assuming the temperature stays constant, what will be the total pressure in the flask after the reaction goes to completion

A) 0.33 atm
B) 0.50 atm
C) 0.67 atm
D) 0.75 atm
E) 1.0 atm

Question 51

A 792 mg sample of a gas containing only sulfur and oxygen occupies a volume of 372 mL at 54 ^$\circ$ C and 678 mmHg. Identify the gas in the sample. (R = 0.08206 L*atm/K*mol)

A) SO
B) SO₂
C) SO₃
D) S₂O
E) S₂O₂

Question 52

A sample of carbon monoxide gas was collected in a 2.0 L flask by displacing water at 28 ^$\circ$ C and 810 mmHg. Calculate the number of CO molecules in the flask. The vapor pressure of water at 28 ^$\circ$ C is 28.3 mmHg.

A) 5.0 * 10²²
B) 5.2 * 10²²
C) 3.8 * 10²³
D) 5.4 * 10²³
E) 3.8 * 10²⁵

Question 53

Which one of these gases is "lighter-than-air"

A) Cl₂
B) SO₂
C) PH₃
D) NO₂
E) Ne

Question 54

Calculate the density of Ar(g) at -11 ^$\circ$ C and 675 mmHg.

A) -39.3 g/L
B) 1.52g/L
C) 1.65 g/L
D) 39.95 g/L
E) 1254 g/L

Question 55

Which of these gases will have the greatest density at the same specified temperature and pressure

A) H₂
B) CClF₃
C) CO₂
D) C₂H₆
E) CF₄

Question 56

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0 ^$\circ$ C. Which of these choices is its molecular formula

A) NO
B) NO₂
C) N₃O₆
D) N₂O₄
E) N₂O₅

Question 57

A 1.17 g sample of an alkane hydrocarbon gas occupies a volume of 674 mL at 28 ^$\circ$ C and 741 mmHg. Alkanes are known to have the general formula C_nH_2n+2. What is the molecular formula of the gas in this sample (R = 0.08206 L * atm/K * mol)

A) CH₄
B) C₂H₆
C) C₃H₈
D) C₄H₁₀
E) C₅H₁₂

Question 58

A mixture of three gases has a total pressure of 1,380 mmHg at 298 K. The mixture is analyzed and is found to contain 1.27 mol CO₂, 3.04 mol CO, and 1.50 mol Ar. What is the partial pressure of Ar

A) 0.258 atm
B) 301 mmHg
C) 356 mmHg
D) 5,345 mmHg
E) 8,020 mmHg

Question 59

A 1.07 g sample of a Noble gas occupies a volume of 363 mL at 35 ^$\circ$ C and 678 mmHg. Identify the Noble gas in this sample. (R = 0.08206 L*atm/K*mol)

A) He
B) Ne
C) Ar
D) Kr
E) Xe

Question 60

2.0 L of gas A at 1.0 atm and 1.0 L of gas B at 1.0 atm are combined in a 3.0 L flask. The flask is sealed and over time they react completely to give gas C according to the following chemical equation: 2A(g) + B(g) $\rarr$ C(g)
Assuming the temperature stays constant, what will be the pressure after the reaction goes to completion

A) 0.33 atm
B) 0.50 atm
C) 0.67 atm
D) 0.75 atm
E) 1.0 atm

Question 61

Which statement is false

A) The average kinetic energies of molecules from samples of different "ideal" gases are the same at the same temperature.
B) The molecules of an ideal gas are relatively far apart.
C) All molecules of an ideal gas have the same kinetic energy at constant temperature.
D) Molecules of a gas undergo many collisions with each other and the container walls.
E) Molecules of greater mass have a lower average speed than those of less mass at the same temperature.

Question 62

Liquid nitrogen has a density of 0.807 g/mL at -195.8 ^$\circ$ C. If 1.00 L of N₂(l) is allowed to warm to 25 ^$\circ$ C at a pressure of 1.00 atm, what volume will the gas occupy (R = 0.08206 L*atm/K*mol)

A) 59.1 L
B) 182 L
C) 705 L
D) 1.41 * 10³ L
E) 1.97 * 10⁴ L

Question 63

9.45 g of liquid hexane (C₆H₁₄) is introduced into a 10.0 L vessel containing 13.15 atm of oxygen gas at 21ºC and ignited, yielding carbon dioxide and water. If the vessel is then cooled to -10.ºC, what will be the gas pressure inside the vessel

A) 1.42 atm
B) 3.09 atm
C) 10.9 atm
D) 12.6 atm
E) 13.15 atm

Question 64

The molecules of different samples of an ideal gas have the same average kinetic energies, at the same

A) pressure.
B) temperature.
C) volume.
D) density.

Question 65

5.00 g of hydrogen gas and 50.0 g of oxygen gas are introduced into an otherwise empty 9.00 L steel cylinder, and the hydrogen is ignited by an electric spark. If the reaction product is gaseous water and the temperature of the cylinder is maintained at 35ºC, what is the final gas pressure inside the cylinder

A) 0.92 atm
B) 2.58 atm
C) 6.96 atm
D) 7.86 atm
E) 18.3 atm

Question 66

What mass of KClO₃ must be decomposed to produce 126 L of oxygen gas at 133 ^$\circ$ C and 0.880 atm (The other reaction product is solid KCl.)

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

Question 67

What volume of O₂(g) at 810. mmHg pressure is required to react completely with a 4.50g sample of C(s) at 48 ^$\circ$ C
2 C(s) + O₂(g) $\rarr$ 2 CO(g)

A) 1.22 L
B) 3.47 L
C) 4.63 L
D) 9.26 L
E) 111 L

Question 68

Which of these gas molecules has the highest average kinetic energy at 25 ^$\circ$ C

A) H₂
B) O₂
C) N₂
D) Cl₂
E) All the gases have the same average kinetic energy.

Question 69

When active metals such as magnesium are immersed in acid solution, hydrogen gas is evolved. Calculate the volume of H₂(g) at 30.1 ^$\circ$ C and 0.85 atm that can be formed when 275 mL of 0.725 M HCl solution reacts with excess Mg to give hydrogen gas and aqueous magnesium chloride.

A) 3.4 * 10^-3 L
B) 2.2 L
C) 2.9 L
D) 5.8 L
E) 11.7 L

Question 70

10.0 g of gaseous ammonia and 6.50 g of oxygen gas are introduced into a previously evacuated 5.50 L vessel. If the ammonia and oxygen then react to yield NO gas and water vapor, what is the final density of the gas mixture inside the vessel at 23ºC

A) 1.32 g/L
B) 1.68 g/L
C) 2.20 g/L
D) 3.00 g/L
E) 16.5 g/L

Question 71

Which gas has molecules with the greatest average molecular speed at 25 ^$\circ$ C

A) CH₄
B) Kr
C) N₂
D) CO₂
E) Ar

Question 72

Calculate the volume of H₂(g) at 273 K and 2.00 atm that will be formed when 275 mL of 0.725 M HCl solution reacts with excess Mg to give hydrogen gas and aqueous magnesium chloride.

A) 0.56 L
B) 1.12 L
C) 2.23 L
D) 3.54 L
E) 4.47 L

Question 73

What is the pressure of the gas trapped in the apparatus shown below when the atmospheric pressure is 720 mmHg ?

A) 12 mmHg
B) 708 mmHg
C) 720 mmHg
D) 732 mmHg
E) 760 mmHg

Question 74

Determine the pressure of the gas trapped in the apparatus shown below when the atmospheric pressure is 695 mmHg.

A) 45 mmHg
B) 650 mmHg
C) 695 mmHg
D) 740 mmHg
E) 760 mmHg

Question 75

Deviations from the ideal gas law are greater at

A) low temperatures and low pressures.
B) low temperatures and high pressures.
C) high temperatures and high pressures.
D) high temperatures and low pressures.

Question 76

How many liters of oxygen gas at 153 ^$\circ$ C and 0.820 atm can be produced by the decomposition of 22.4 g of solid KClO₃ (The other decomposition product is solid potassium chloride.)

A) 0.085 L
B) 3.0 L
C) 4.20 L
D) 7.79 L
E) 11.7 L

Question 77

10.0 g of gaseous ammonia and 6.50 g of oxygen gas are introduced into a previously evacuated 5.50 L vessel. If the ammonia and oxygen then react to yield NO gas and water vapor, what is the final gas pressure inside the vessel at 23ºC

A) 0.285 atm
B) 1.79 atm
C) 3.50 atm
D) 3.67 atm
E) 6.48 atm

Question 78

For a substance that remains a gas under the conditions listed, deviation from the ideal gas law would be most pronounced at

A) 100 ^$\circ$ C and 2.0 atm.
B) 0 ^$\circ$ C and 2.0 atm.
C) -100 ^$\circ$ C and 2.0 atm.
D) -100 ^$\circ$ C and 4.0 atm.
E) 100 ^$\circ$ C and 4.0 atm.

Question 79

How many liters of chlorine gas at 25 ^$\circ$ C and 0.950 atm can be produced by the reaction of 12.0 g of MnO₂ with excess HCl(aq) according to the following chemical equation
MnO₂(s) + 4HCl(aq) $\rarr$ MnCl₂(aq) + 2H₂O(l) + Cl₂(g)

A) 5.36 * 10^-3 L
B) 0.138 L
C) 0.282 L
D) 3.09 L
E) 3.55 L

Question 80

If equal masses of O₂(g) and HBr(g) are in separate containers of equal volume and temperature, which one of these statements is true

A) The pressure in the O₂ container is greater than that in the HBr container.
B) There are more HBr molecules than O₂ molecules.
C) The average velocity of the O₂ molecules is less than that of the HBr molecules.
D) The average kinetic energy of HBr molecules is greater than that of O₂ molecules.
E) The pressures of both gases are the same.