Dr. Bundey Gas Laws
Modified from Mr.Lavine 1/2017
Name
Date
Period
12. What is used as a foundation for many basic
mathematical descriptions of gases?
Engage
13. Describe the volume of the particles of an ideal gas.
14. What is the particle kinetic energy dependent on for an
ideal gas?
15. Describe the range of pressures and temperatures that
real gases behave as ideal gases.
16. What equation defines pressure.
17. What are three units of pressure?
A hiker brings a bag of chips from sea level to the top of a
mountain. The bag appears to swell and increase in volume.
1. Explain what you think is happening to the bag of chips in
this process.
2. Predict what would happen to the bag of chips if you took it
to the bottom of a pool.
3. Predict what would happen to the bag of chips if you were
to heat it up.
4. Predict what would happen if the bag of chips if you were
to place it in the freezer.
18. Where are air molecules most concentrated in the
atmosphere of the earth?
19. Which early scientist tried to duplicate the hot air balloon
flight of Mongolfier?
20. What relationship did Jacques-Alexandre-Cesar Charles
develop as a result of his experience with hot air balloons and
subsequent experiments?
21. What can be extrapolated from the volume vs. absolute
temperature data?
22. What is the value of absolute zero in °C?
23. What equation defines Charlesʼ Law?
Explore
5. Describe the characteristics of a gas.
24. What did Boyleʼs most famous experiments deal with?
6. Dos a gas have a definite shape or volume?
25. What was the relationship Boyle noticed between
pressure and volume?
7. Are gases compressible?
26. What equations define Boyleʼs Law?
8. What volume does one mole of an ideal gas occupy at
STP?
9. How many particles of an ideal gas are present in 22.4 L of
space?
27. Who discovered the relationship between the pressure
and temperature of a fixed mass of gas kept at a constant
volume?
10. Will 22.4 L of helium gas have the same mass as 22.4 L
of nitrogen gas at STP?
28. What is the relationship between pressure and
temperature for a fixed volume of a gas?
11. Will 22.4 L of helium gas have the same number of
particles as 22.4 L of nitrogen gas at STP?
29. Write an equation describing the combined gas law.
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32. The contents of a fire extinguisher are under 91.5
atmospheres of pressure at 18.0°C. The temperature of the
fire extinguisher rises to 45.0°C on a hot day. Assume no
change in volume. Determine the final pressure in the fire
extinguisher.
a. List provided terms
P1 =
30. 1. A 3.55 L helium balloon at 101,325 Pa is released at
sea level and rises to a height where the pressure is 9.50
4
x10 Pa. Assume no change in temperature. Determine the
final volume of the balloon.
a. List provided terms
V1 =
P1 =
T1 =
P2 =
T2 =
b. Record the relevant equation
V2 =
P2 =
b. Record the relevant equation
c. Perform the necessary algebra to isolate the desired term.
c. Perform the necessary algebra to isolate the desired term.
d. Substitute in the values and solve the problem.
d. Substitute in the values and solve the problem.
31. A tire has a volume of 4.55 L at 22.0°C. The temperature
increases to 42.0°C. Assume no change in temperature.
Determine the final volume of the tire.
a. List provided terms
V1 =
33. A person sits on an inflatable seat cushion, compressing
it. The initial volume is 2.44 L. The initial temperature is
20.0°C. The initial pressure is 102,000 Pa. The final pressure
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is 1.20 x 10 Pa. The final temperature is 29°C. Determine the
final volume of the cushion.
P1 =
T1 =
V1 =
P2 =
T2 =
V2 =
b. Record the relevant equation
T1 =
V2 =
T2 =
b. Record the relevant equation
c. Perform the necessary algebra to isolate the desired term.
c.
d. Substitute in the values and solve the problem.
Perform the necessary algebra to isolate the desired term.
d. Substitute in the values and solve the problem.
2
Notes
I. Gas Phase
A.
1. No definite shape or volume.
a. Gases are compressible.
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b. At STP 1 mole of particles (6.02 x 10 ) occupies 22.4 L of space.
B. Ideal Gas
1. The “Ideal Gas” model is used as a foundation for many basic mathematical descriptions of gases.
2. Ideal gases are defined as having molecules with negligible size with an average molar kinetic energy dependent only on
temperature.
a. Actual gases behave as ideal gases only within a relatively small temperature and pressure range.
b. For Chemistry 1,2, we will treat all gases as ideal gases.
II. Pressure
A. Pressure=Force/unit area
2
1. Pascals=Newtons/meter
2. 1 Atmosphere = 101,325 pascals
3. 1 Atmosphere = 760 mm Hg
3
a.
4. 1 Atmosphere = 14.7 PSI (pounds per square inch)
B. Atmospheric Pressure Patterns
II. Gas Laws
A. Charles Law
1. On 5 June 1783, Joseph Montgolfier used a fire to inflate a spherical balloon about 30 feet in diameter that traveled about a
mile and one-half before it came back to earth.
2. News of this remarkable achievement spread throughout France, and Jacques-Alexandre-Cesar Charles immediately tried
to duplicate this performance.
Jacques-Alexandre-Cesar Charles
1746-1823
3. As a result of his work with balloons, Charles noticed that the volume of a gas is directly proportional to its temperature.
a. V∝T
b. V1/T1=V2/T2
c.
i. The value of absolute zero can be extrapolated from the experimental V vs. T data.
4. This relationship between the temperature and volume of a gas, which became known as Charles' law, provides an
explanation of how hot-air balloons work.
a. Ever since the third century B.C., it has been known that an object floats when it weighs less than the fluid it displaces.
b. If a gas expands when heated, then a given weight of hot air occupies a larger volume than the same weight of cold air.
c. Hot air is therefore less dense than cold air.
d. Once the air in a balloon gets hot enough, the net weight of the balloon plus this hot air is less than the weight of an
equivalent volume of cold air, and the balloon starts to rise.
e. When the gas in the balloon is allowed to cool, the balloon returns to the ground.
B. Boyle’s Law
Robert Boyle
1627-1691
1. Torricelli's work with a vacuum caught the eye of the British scientist Robert Boyle.
2. Boyle's most famous experiments with gases dealt with what he called the "spring of air."
3. These experiments were based on the observation that gases are elastic. (They return to their original size and shape after
being stretched or squeezed.)
4. Boyle studied the elasticity of gases in a J-tube similar to the apparatus shown below.
5. By adding mercury to the open end of the tube, he trapped a small volume of air in the sealed end.
6. Boyle studied what happened to the volume of the gas in the sealed end of the tube as he added mercury to the open end.
7. Boyle noticed that the product of the pressure times the volume for any measurement in this table was equal to the product
of the pressure times the volume for any other measurement, within experimental error.
a. P1V1 = P2V2
b. This expression, or its equivalent,
P ∝1/V is now known as Boyle's Law.
C. Amontons’ Law
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