Deck 13: Gases

Question 1

Convert atm to torr.

A) torr
B) 1.289 torr
C) 68.1 torr
D) torr
E) torr

Answer 1

torr

Question 2

Convert torr to psi.

A) 1.08 psi
B) 15.9 psi
C) psi
D) psi
E) psi

Answer 2

15.9 psi

Question 3

Consider a gas at 1.00 atm in a 5.00-L container at 20.°C. What pressure does the gas exert when transferred to a volume of 2.77 L at 43°C?

A) 3.88 atm
B) 1.67 atm
C) 0.371 atm
D) 1.95 atm
E) 0.597 atm

Answer 3

1.95 atm

Question 4

You have a sample of argon gas at a certain pressure, volume, and temperature. You double the volume, double the number of moles of argon, and double the Kelvin temperature. How does the final pressure (P_f) compare to the original pressure (P_o)? P_f =

A) (1/8)P_o
B) (1/2)P_o
C) 2P_o
D) 4P_o
E) 8P₂

Question 5

What is the volume of a helium balloon that contains 1.95 mol helium at 27°C and 1.10 atm?

A) 3.93 L
B) 39.7 L
C) 48.0 L
D) 43.6 L
E) 4.32 L

Question 6

Perform the following conversion of pressure units: Pa = ____________ atm

A)
B)
C)
D)
E)

Question 7

Consider a sample of gas in a container on a comfortable spring day in Chicago, IL. The Celsius temperature suddenly doubles, and you transfer the gas to a container with twice the volume of the first container. If the original pressure was 11 atm, what is a good estimate for the new pressure?

A) 12 atm
B) 2.8 atm
C) 5.9 atm
D) 11 atm
E) 22 atm

Question 8

Perform the following conversion of pressure units: 193 torr = ____________ atm

A) 1.91
B) 13.1
C) 0.254
D) 3.94
E) 953

Question 9

When analyzing ideal gases, the temperature must be measured on the Kelvin scale

A) because otherwise you could calculate a negative volume.
B) so that you are using an absolute scale.
C) to directly measure the average kinetic energy of the gas particles.
D) Both a and b are correct.
E) a, b, and c are correct.

Question 10

Perform the following conversion of pressure units: torr = ___________ atm

A)
B)
C)
D)
E)

Question 11

Determine the pressure exerted by 2.26 mol of gas in a 2.92-L container at 32°C.

A) 2.03 atm
B) 56.6 atm
C) 19.4 atm
D) 5.93 atm
E) 17.3 atm

Question 12

You are playing with a helium balloon on a typically warm California day. Suddenly, the Celsius temperature doubles. Which of the following is true?

A) The volume of the balloon will double.
B) The volume of the balloon will slightly increase.
C) The pressure inside the balloon will double.
D) The volume of the balloon will decrease.
E) The actual temperatures are needed to answer this question.

Question 13

Perform the following conversion of pressure units: 232 kPa = ____________ Pa

A) 0.232
B)
C) 2.32
D)
E)

Question 14

A 15.0-g sample of a hydrocarbon is placed in a balloon at 1.00 atm and 25°C, and the volume of the balloon is 12.2 L. The hydrocarbon is 79.89% carbon and 20.11% hydrogen by mass. Determine the molecular formula of the hydrocarbon.

Question 15

Perform the following conversion of pressure units: 0.875 atm = ____________ torr

A) 869
B) 88.6
C) 12.9
D) 665
E) 690

Question 16

A certain balloon will pop if it expands to a volume greater than 16.0 L. The balloon is currently filled with air at a volume of 8.0 L. You heat the balloon such that the temperature measured in degrees Celsius doubles. Which of the following best describes what happens?

A) The balloon will expand to a volume greater than 16.0 L and pop.
B) The balloon will expand to a volume less than 16.0 L and not pop.
C) The balloon will expand to a volume of 16.0 L and pop.
D) The balloon will expand to a volume of 16.0 L and not pop.
E) The volume of the balloon will remain the same but the pressure will increase.

Question 17

You are holding two helium balloons, a large and a small balloon. How do the pressures of the helium compare?

A) The pressure in the large balloon is greater than the pressure in the small balloon. This is best explained by the fact that there must be more moles of gas in the large balloon, thus greater pressure.
B) The pressure in the small balloon is greater than the pressure in the large balloon. This is best explained by the fact that as the volume of a container decreases, the pressure of the gas increases.
C) The pressure in the large balloon is greater than the pressure in the small balloon. The fact that there is a greater pressure in the balloon explains why the volume is larger; as the particles push more on the inside, the volume increases.
D) The pressures are essentially the same and less than atmospheric pressure.
E) The pressures are essentially the same and equal to atmospheric pressure.

Question 18

The air in the inner tube of the tire of a racing bike has a pressure of 116.8 psi. Convert this pressure to atm.

A) 0.1537 atm
B) 7.946 atm
C) 1717 atm
D) 1.153 atm
E) 116.8 atm

Question 19

A gaseous compound containing carbon and hydrogen was analyzed and found to consist of between 80 and 90 percent carbon by mass. At 145ºC and 1.00 atm, the density of this compound is 2.45 g/L. What is the molar mass of the compound?

A) 84.2 g/mol
B) 29.2 g/mol
C) 55.0 g/mol
D) 99.1 g/mol
E) 42.1 g/mol

Question 20

Perform the following conversion of pressure units: 1.177 atm = ____________ torr

A) 894.5
B) 645.7
C)
D) 17.30
E) 1.177

Question 21

You are holding two balloons, an orange balloon and a blue balloon. The orange balloon is filled with neon (Ne) gas, and the blue balloon is filled with argon (Ar) gas. The orange balloon has twice the volume of the blue balloon. Which of the following best represents the mass ratio of Ne:Ar in the balloons?

A) 1:1
B) 1:2
C) 2:1
D) 1:3
E) 3:1

Question 22

Suppose a balloon has a maximum volume of 7.00 L. Also suppose each time you blow into a balloon, you expel 0.045 mol of air. How many times can you blow into the balloon before the balloon pops? Assume atmospheric conditions of 1.0 atm and 22°C and that your breath is at room temperature.

Question 23

A sample of helium gas occupies 14.3 L at 23°C and 0.956 atm. What volume will it occupy at 40.°C and 0.956 atm?

A) 24.9 L
B) 0.0661 L
C) 13.5 L
D) 15.1 L
E) none of these

Question 24

A sample of an ideal gas containing 0.637 mol is collected at 742 torr pressure and 31°C. Calculate the volume.

A) 16.3 L
B) 1.66 L
C) L
D) L
E) none of these

Question 25

You are holding four balloons, each containing 6.0 g of a different gas. The balloon containing which gas is the largest?

A) He
B) Ne
C) Kr
D) N₂
E) All have the same volume.

Question 26

Which of the following statements is true of 19.0 g of F₂(g) at STP?

A) It contains 6.02 * 10²³ molecules.
B) It contains the same number of molecules as mol of O₂(g) at STP.
C) It occupies a volume of 22.4 L.
D) It exists only in the form of ions.
E) none of the above

Question 27

A gas originally occupying 10.1 L at 0.925 atm and 25°C is changed to 13.3 L at 625 torr. What is the new temperature?

A) 349 °C
B) 76 °C
C) -244 °C
D) 622 °C
E) 50 °C

Question 28

A 12.0-g sample of helium gas occupies a volume of 14.4 L at a certain temperature and pressure. What volume does a 24.0-g sample of neon occupy at these conditions of temperature and pressure?

A) 5.71 L
B) 28.8 L
C) 22.4 L
D) 36.3 L
E) 11.4 L

Question 29

You fill a balloon with 10.0 g of N₂ gas. You wish to add 10.0 g of another gas to make the balloon more than twice as large as it is with only the N₂ (that is, more than twice the original volume). Which gas should you add (assume constant temperature)?

A) O₂
B) CO₂
C) CO
D) He
E) You cannot make the balloon more than twice as large with 10.0 g of any gas.

Question 30

Two moles of gas A spontaneously convert to 3 moles of gas B in a container where the temperature and pressure are held constant. The sample originally took up 36.2 L of volume. What is the new volume of the products?

A) 24.1 L
B) 109 L
C) 72.4 L
D) 7.24 L
E) 54.3 L

Question 31

A specified quantity of an unknown gas has the volume of 14.1 mL at 22°C and 659 torr. Calculate the volume at STP.

A) 0.912 mL
B) 13.2 mL
C) 11.3 mL
D) 15.0 mL
E) none of these

Question 32

You are holding two balloons of the same volume. One balloon contains 1.05 g helium. The other balloon contains neon. What is the mass of neon in the balloon?

A) 0.262 g
B) 1.05 g
C) 76.9 g
D) 5.29 g
E) 20.0 g

Question 33

Which of the following will give a graph with a straight line and a y-intercept of 0?

A) volume vs. 1/temperature (°C)
B) volume vs. temperature (°C)
C) volume vs. temperature (K)
D) volume vs. 1/temperature (K)
E) none of these

Question 34

A sample of a gas in a container fitted with a piston has a temperature above 0°C. The Celsius temperature is doubled. What is true about the ratio of final volume to initial volume for the gas?

A) It is 1:1.
B) It is 2:1.
C) It is 1:2.
D) It is greater than 2:1.
E) It is less than 2:1.

Question 35

Which of the following statements are true of real gases?

A) A real gas behaves more like an ideal gas at high pressures and low temperatures.
B) The individual gas particles have no volume.
C) The individual gas particles are not attracted to one another.
D) The particles collide with the walls of its container and exert pressure.
E) The kinetic energy of the gas particles is directly proportional to the temperature of the gas in degrees Celsius.

Question 36

If temperature and pressure are held constant, the volume and number of moles of a gas are

A) independent of each other
B) directly proportional
C) inversely proportional
D) equal
E) not enough information given

Question 37

You have a partially filled party balloon with 2.00 g of helium gas. You then add 3.00 g of hydrogen gas to the balloon. Assuming constant temperature and pressure, how many times bigger is the party balloon - comparing before and after the hydrogen gas has been added. Choose the best formula to use to solve this problem. (V = volume of the gas, n = moles of the gas, m = mass of the gas, P = pressure of the gas.)

A)
B)
C)
D)
E)

Question 38

You transfer a sample of gas at 17°C from a volume of 5.68 L and 1.10 atm to a container at 37°C that has a pressure of 1.10 atm. What is the new volume of the gas?

A) 12.4 L
B) 6.07 L
C) 5.31 L
D) 0.165 L
E) none of these

Question 39

You have a certain mass of helium gas in a rigid steel container. You add the same mass of neon gas to this container. Which of the following best describes what happens? Assume temperature is constant.

A) The pressure in the container doubles.
B) The pressure in the container increases but does not double.
C) The pressure in the container more than doubles.
D) The volume of the container doubles.
E) The volume of the container more than doubles.

Question 40

Gaseous chlorine is held in two separate containers at identical temperature and pressure. The volume of container 1 is 1.30 L, and it contains 6.70 mol of the gas. The volume of container 2 is 2.77 L. How many moles of the gas are in container 2?

A) 14.3 mol
B) mol
C) 3.14 mol
D) 4.07 mol
E) none of these

Question 41

Zinc metal is added to hydrochloric acid to generate hydrogen gas and is collected over a liquid whose vapor pressure is the same as that of pure water at 20.0°C (18 torr). The volume of the mixture is 1.7 L, and its total pressure is 0.508 atm. Determine the partial pressure of the hydrogen gas in this mixture.

A) 404 torr
B) 656 torr
C) 368 torr
D) 626 torr
E) 386 torr

Question 42

A gas occupies 42.6 L at 2.00 atm pressure and 27°C. Calculate its volume if the pressure is decreased to 1.00 atm at constant temperature.

A) 21.3 L
B) 85.2 L
C) 128 L
D) 28.5 L
E) 179 L

Question 43

A vessel with an internal volume of 15.3 L contains 2.80 g of nitrogen gas, 0.403 g of hydrogen gas, and 79.9 g of argon gas. At 25^oC, what is the pressure (in atm) inside the vessel?

A) 860 atm
B) 0.308 atm
C) 3.68 atm
D) 0.272 atm
E) 133 atm

Question 44

A 6.08-g piece of solid CO₂ (dry ice) is allowed to vaporize (change to CO₂(g)) in a balloon. The final volume of the balloon is 1.00 L at 300. K. What is the pressure of the gas?

A) 3.40 atm
B) 6.50 atm
C) 0.306 atm
D) 153 atm
E) none of these

Question 45

A gas occupies 32.6 L at 2.00 atm pressure and 27°C. Calculate its volume if the pressure remains at 2.0 atm but the temperature is raised to 54°C.

A) 29.9 L
B) 65.2 L
C) 0.0281 L
D) 35.5 L
E) 23.8 L

Question 46

An oxygen sample has a volume of 7.01 L at 27°C and 800.0 torr. How many oxygen molecules does it contain?

A)
B)
C)
D)
E) none of these

Question 47

A 251-mL sample of a gas at STP is heated to 45°C. The final pressure is 1.86 atm. Calculate the volume of this gas under the new conditions.

A) 22.2 mL
B) 116 mL
C) 8630 mL
D) 157 mL
E) 105 mL

Question 48

A sample of oxygen gas at 70^oC is twice as hot as a sample of oxygen gas at 35^oC.

Question 49

A gas is collected over water at a certain temperature. The total pressure is 758 torr. The vapor pressure of water at this temperature is 17 torr. The partial pressure of the gas collected is

A) 758 torr
B) 17 torr
C) 775 torr
D) 741 torr
E) 733 torr

Question 50

A 16.4-L sample of gas at STP is heated to 55°C at 605 torr. What is the new volume?

A) 24.8 L
B) 4.15 L
C) 17.1 L
D) 15.7 L
E) 16.6 L

Question 51

A gas occupies 18.5 L at STP. What volume will it occupy at 735 torr and 57°C?

A) 3.99 L
B) 21.6 L
C) 15.8 L
D) 15.5 L
E) 23.1 L

Question 52

The volume of a sample of gas is 561.5 mL at STP. What volume will the sample occupy at 0.0°C and 950.0 torr?

A) 701.9 mL
B) 449.2 mL
C) 411.5 mL
D) 561.2 mL
E) none of these

Question 53

What volume will 55.6 g of N₂ occupy at STP?

A) 48.5 L
B) L
C) 44.5 L
D) 4.07 L
E) none of these

Question 54

A gas occupies 33.5 L at 2.00 atm pressure and 27°C. Calculate its volume at STP.

A) 73.6 L
B) 677 L
C) 30.5 L
D) 74.0 L
E) 61.0 L

Question 55

Zinc metal is added to hydrochloric acid to generate hydrogen gas and is collected over a liquid whose vapor pressure is the same as that of pure water at 20.0°C (18 torr). The volume of the mixture is 1.7 L, and its total pressure is 0.788 atm. Determine the number of moles of hydrogen gas present in the sample.

A) 0.792 mol
B) 0.111 mol
C) 0.216 mol
D) 0.0540 mol
E) 0.0318 mol

Question 56

A gas occupies 30.3 L at 2.00 atm pressure and 27°C. How many moles of gas are present in the sample?

A) 27.4 mol
B) 1.23 mol
C) 2.46 mol
D) 3.96 mol
E) 4.86 mol

Question 57

Mercury vapor contains Hg atoms. What is the volume of 200. g of mercury vapor at 822 K and 0.415 atm?

A) 162 L
B) 27.9 L
C) 216 L
D) 108 L
E) 324 L

Question 58

A 4.06-L sample of carbon monoxide is collected at 55°C and 0.892 atm. What volume will the gas occupy at 1.05 atm and 20.°C?

A) 1.25 L
B) 3.86 L
C) 3.08 L
D) 4.27 L
E) none of these

Question 59

What volume is occupied by 22.6 g of methane, CH₄, at 27°C and 1.59 atm?

A) 34.7 L
B) 21.8 L
C) 1.96 L
D) 31.5 L
E) not enough data to calculate

Question 60

A 41.1-mL sample of H₂ at STP would contain how many grams of hydrogen?

A) g
B) 3.70 g
C) 1.83 g
D) g
E) g

Question 61

You have a partially filled party balloon with 2.00 g of helium gas. You then add 3.45 g of hydrogen gas to the balloon. Assuming constant temperature and pressure, how many times bigger is the party balloon - comparing before and after the hydrogen gas has been added?

A) 3.42 times bigger
B) 7.85 times bigger
C) 4.42 times bigger
D) 6.85 times bigger
E) 5.45 times bigger

Question 62

How many liters of HCl(g) measured at STP can be produced from 5.44 g of Cl₂ and excess H₂ according to the following equation?

A) 1.72 L
B) 121.9 L
C) 3.44 L
D) 5.16 L
E) none of these

Question 63

You place 15.0 g of nitrogen gas and 15.0 g of hydrogen gas in a container fitted with a massless, frictionless piston. If the original volume of the container is 11.4 L, what is the volume after the reaction has run to completion? Assume constant temperature. N₂(g) + 3H₂(g) $\rightarrow$ 2NH₃(g)

A) 13.17 L
B) 1.53 L
C) 7.09 L
D) 9.87 L
E) 1.32 L

Question 64

You transfer a gas at 25^oC from a volume of 2.49 L and 0.950 atm to a vessel at 32^oC which has a volume of 8.75 L. What is the new pressure of the gas?

A) 0.346 atm
B) 0.264 atm
C) 3.42 atm
D) 0.291 atm
E) 0.277 atm

Question 65

Which of the following statements is true about the kinetic molecular theory?

A) The volume of a gas particle is considered to be small: about 0.10 mL.
B) Pressure is due to the collisions of the gas particles with the walls of the container.
C) Gas particles repel each other but do not attract one another.
D) Adding an ideal gas to a closed container will cause an increase in temperature.
E) At least two of these statements are correct.

Question 66

How many moles of O₂(g) are needed to react completely with 51.2 L of CH₄(g) at STP to produce CO₂(g) and H₂O(g) according to the following reaction?

A) 4.57
B)
C) 1.14
D) 2.29
E) none of these

Question 67

A compressed gas cylinder, at 137 atm and 23^oC, is in a room where a fire occurs. The fire raises the temperature of the gas to 475^oC. What is the new pressure in the cylinder?

A) atm
B) 3.30 atm
C) 85.4 atm
D) atm
E) 2.16 atm

Question 68

When acetylene gas, C₂H₂, burns, how many liters of O₂ at STP are used for every 9.31 mol of acetylene burned? (Hint: Write the balanced equation for the reaction first.)

A) 209 L
B) 417 L
C) 83.4 L
D) 23.3 L
E) 521 L

Question 69

A sample of argon gas occupies a certain volume at 15^oC. At what temperature would the volume of the gas be three times as big? Assume the pressure remains constant.

A) 864^oC
B) 45^oC
C) 318^oC
D) 591^oC
E) 1137^oC

Question 70

A sample of oxygen gas (O₂) has a volume of 7.08 L at a temperature of 19^oC and a pressure of 1.38 atm. Calculate the moles of O₂ molecules present in this gas sample.

A) 6.27 mol
B) 0.408 mol
C) 0.816 mol
D) 0.204 mol
E) none of these

Question 71

Solid carbon dioxide is placed into a Ziploc bag. Solid carbon dioxide sublimes (turns directly from a solid to a gas) at a rate of 0.726 g/minute. If the pressure builds to 3.75 atm at a temperature of 21.1^oC, what is the final volume of the bag after 4.97 minutes? (Assume the volume of the solid carbon dioxide is negligible.)

A) 37.9 mL
B) 0.379 mL
C) 1.98 mL
D) 0.528 mL
E) 528 mL

Question 72

Hydrogen peroxide decomposes to form water and oxygen gas according to the following equation: Suppose 145.9 g of hydrogen peroxide decomposes and all of the oxygen gas is collected in a balloon at 1.00 atm and 25^oC. Determine the volume of the balloon.

A) 4.40 L
B) 104.9 L
C) 52.4 L
D) 8.80 L
E) none of these

Question 73

The largest a party balloon can get before bursting is 8.55 L at 25^oC and 1.00 atm. Supposing you fill the balloon only with oxygen gas, how many grams of oxygen can be added to the balloon before it pops? Assume you have not yet added any gas to the balloon at all (so essentially the balloon is flat).

A) 11.2 g O₂
B) 0.350 g O₂
C) 4.17 g O₂
D) 133 g O₂
E) 2.86 g O₂

Question 74

You carry out the reaction represented by the following equation:
N₂(g) + 3H₂(g) $\rightarrow$ 2NH₃(g)
You add an equal number of moles of nitrogen gas and hydrogen gas in a balloon. The volume of the balloon is 2.65 L before any reaction occurs. Determine the volume of the balloon after the reaction is complete.
a.
0.883 L
b.
1.77 L
c.
2.65 L
d.
0.442 L
e.
3.53 L

Question 75

There are two balloons, both the same size and temperature. One balloon contains hydrogen and the other balloon contains carbon dioxide. The hydrogen balloon floats, and the carbon dioxide balloon sinks in the air. How do the pressures inside of the two balloons compare?

A) The carbon dioxide balloon has a greater pressure than the hydrogen balloon.
B) The hydrogen balloon has a greater pressure than the carbon dioxide balloon.
C) The pressures in both balloons are essentially the same.
D) This problem cannot be solved without more information given.

Question 76

Solid carbon dioxide is placed into a Ziploc bag. At a certain temperature, solid carbon dioxide sublimes (turns directly from a solid to a gas) at a rate of 0.726 g/minute. How many gaseous carbon dioxide molecules are present after 4.84 minutes?

A)
B)
C)
D)
E)

Question 77

A flexible weather balloon contains helium gas at a volume of 855 L. Initially, the balloon is at sea level, where the temperature is 25^oC and the barometric pressure is 0.947 atm. The balloon then rises to an altitude of 5500 ft, where the pressure is 0.785 atm and the temperature is 15^oC. What is the change in the volume of the balloon as it ascends from sea level to 5500 ft?

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

Question 78

Which conditions of P and T are most ideal for a gas?

A) high P, high T
B) high P, low T
C) low P, high T
D) low P, low T
E) depends on the gas

Question 79

There are two balloons, both the same size and temperature. One balloon contains hydrogen and the other balloon contains carbon dioxide. The hydrogen balloon floats, and the carbon dioxide balloon sinks in the air. Which balloon contains a greater number of molecules?

A) The carbon dioxide balloon contains a greater number of molecules.
B) The hydrogen balloon contains a greater number of molecules.
C) Both balloons contain the same number of molecules.
D) This problem cannot be solved without more information given.

Question 80

What volume of HCl(g) measured at STP can be produced from 1.91 g of H₂ and excess Cl₂ according to the following equation?

A) 21.2 L
B) 42.4 L
C) 86 L
D) 173 L
E) 64.2 L