X Unit 14 –
Gas Laws
Homework & Handouts
Miss Adams
Name: ______________________________
Period: ________
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Homework #1: Pressure Conversions
Convert the following pressures to the indicated units. SHOW ALL WORK!!
1. 6.2 atm = ? torr
7. 48 mmHg = ? torr
2. 1.2 atm = ? kPa
8. 600 mmHg = ? kPa
3. 2.7 atm = ? torr
9. 0.62 atm = ? mmHg
4. 105.6 mmHg = ? torr
10. 3.22 atm = ? kPa
5. 850 torr = ? atm
11. 526 mmHg = ? kPa
6. 1820 mmHg = ? atm
12. 192 kPa = ? torr
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Homework #2: Boyle’s Law
Use Boyle’s Law to answer the following questions:
1)
1.00 L of a gas at standard temperature (0 deg. C) and pressure (1.00 atm) is compressed to
473 mL. What is the new pressure of the gas in atm?
2)
Synthetic diamonds can be manufactured at pressures of 6.00 x 10 4 atm. If we took 2.00 liters
of gas at 760 torr and compressed it to a pressure of 6.00 x 104 atm, what would the volume
of that gas be in mL?
3)
Submarines need to be extremely strong to withstand the extremely high pressure of water
pushing down on them. An experimental research submarine with a volume of 15,000 liters
has an internal pressure of 1.2 atm. If the pressure of the ocean breaks the submarine
forming a bubble with a pressure of 250 atm pushing on it, how big will that bubble be in L?
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HW #3: Charles’ Law
Use Charles’ Law to answer the following questions:
1)
A man heats a balloon in the oven. If the balloon initially has a volume of 400.0 mL and a
temperature of 20 0C, what will the volume of the balloon be in L after he heats it to a
temperature of 250 0C?
2)
On hot days, you may have noticed that potato chip bags seem to “inflate”, even though they
have not been opened. If I have a 250 mL bag at a temperature of 19 0C, and I leave it in my
car which has a temperature of 600 C, what will the new volume of the bag be?
3)
A soda bottle is flexible enough that the volume of the bottle can change even without
opening it. If you have an empty soda bottle (volume of 2.0 L) at room temperature (25 0C),
what will the new volume be in mL if you put it in your freezer (-4 0C)?
4)
I place a balloon in my fridge that initially has a temperature of 22 0 C and an initial volume of
0.5 liters. Once the balloon reaches the temperature of the refrigerator, I measure the final
volume as 0.47 L. What is the final temperature of my refrigerator in Kelvin? In °C?
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HW #4: Gay-Lusaac’s Law
Use Gay-Lusaac’s Law to answer the following problems. Show your work!!
1) Before a trip from New York to Boston, the pressure in an automobile tire is 1.8 atm at 20°C. At
the end of the trip, the pressure gauge reads 1.9 atm. What is the new Celsius temperature of the air
inside the tire?
2) At 120°C, the pressure of a sample of nitrogen is 1.07 atm. What will the pressure by at 205°C
assuming constant volume and number of molecules?
3) An empty aerosol can at room temperature (20°C) is thrown into an incinerator where the
temperature reaches 500°C. If the gas inside the empty container was initially at a pressure of 1.0
atm, what pressure did it reach inside the incinerator? Assume the gas was at constant volume and
the can did not explode.
4) If the sun heats my car from a temperature of 200 C to a temperature of 550 C, what will the
pressure inside my car be? Assume the pressure was initially 760 mm Hg.
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HW #5: Mixed Gas Laws
Change the following units: 359 kPa = _________ atm
6.2 atm = ________ kPa
10C = ________ K
10 K = _______ C
Directions: Decide which law to use and WRITE OUT the law along with its name. Next, designate each
value from the problem as either P1, P2, V1, V2, T1, or T2 depending on which law you use. Then, setup
your problem and solve!
1. The gas in a sealed can is at a pressure of 3.00 atm at 25C. A warning on the can tells not to store the
can in a place where the temperature will exceed 52C. What would the pressure in the can be at 52C?
3. A sample of neon gas occupies a volume of 752 mL at 25C. What volume will the gas occupy at
standard temperature if the pressure remains constant?
4. A sample of oxygen gas has a volume of 150 mL when its pressure is 440 mmHg. If the pressure is
increased to standard pressure and the temperature remains constant, what will the new gas volume be?
5. Ralph had a helium balloon with a volume of 4.88 liters at 150 kPa of pressure. If the volume is
changed to 3.15 liters, what would be the new pressure in atm?
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HW #6: Combined Gas Law
Solve the following problems using the combined gas law. Show all work and pay attention to units!
1) A gas occupies a volume of 2.5 liters at 596 K and 1 atm pressure. What will its new volume be if
the temperature decreases to 298 K and the pressure is raised to 3 atm?
2) If a gas occupies a volume of 5 liters at 546 K and 2.5 atm, what is its volume at STP? (Hint: look in
your notes! STP corresponds to a specific temperature and a specific pressure!)
3) Seaweed plants release oxygen gas during photosynthesis. A 0.10 mL bubble is released under
water at a pressure of 176 kPa and a temperature of 10°C. What volume will this bubble occupy at
the surface, where the temperature is 15°C and the pressure is 55 kPa?
4) A gas storage tank has a volume of 3.5 x 105 mL when the temperature is 27°C and the pressure is
1.0 atm. What is the new volume of the tank if the temperature drops to -10°C and the pressure
drops to 0.95 atm?
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Homework #7: Ideal Gas Law
Show all work and pay special attention to the units. Remember, you must match the units to the
units in the ideal gas constant!!
1. If the pressure exerted by a gas at 25°C in a volume of 44 mL is 3.81 atm, how many moles of gas
are present?
2. What is the pressure in mm Hg of a 0.108 mol sample of helium gas at a temperature of 20.0°C, if
its volume is 505 mL?
3. Determine the temperature required for a 0.09494 g sample of hydrogen gas (H2) to fill a balloon
to 1.20 L under 0.988 atm pressure.
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HW #8: Mixed Review Problems
For the following problems, first decide which law you need to use (Boyle’s, Charles’, Gay-Lusaac’s,
Combined, or Ideal) and then set up your problem and solve.
1. A 70. liter sample of gas initially at 280 oC is allowed to cool at constant pressure, what will the
new volume be at 0 oC?
2. It is not safe to put aerosol canisters in a campfire because the pressure inside the canisters gets
very high and it can explode. If I have a 1500 mL canister which contains 16.0 grams of hydrogen
gas and the campfire temperature is 1400°C, what is the pressure inside the canister?
3. A sample of oxygen gas has a volume of 150 mL when its pressure is 440 mmHg. If the pressure is
increased to 760 mmHg and the temperature remains constant, what will the new gas volume
be?
4. At a pressure of 780 mmHg and 24.2 ˚C, a certain gas has a volume of 350 mL. What will the
volume of this gas be at STP?
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5. A sample of gas at 15 oC has a volume of 2.58 L. What volume will this gas occupy at 38 oC?
6. How many moles of gas are in a scuba tank if the temperature of the tank is 30°C and the
pressure is 200 atm? The volume of the tank is 7 liters.
7. At a pressure of 405 kPa, the volume of a gas is 6.00 mL. Assuming the temperature remains
constant, at what pressure will the new volume be 4.00 mL?
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