Gas Law Unit Plan Outline
Yimin Tang
Date
Day 1
Day 2
Day 3
Day 4
Day 5
Lesson
Property of Gas
Pressure
NSTA Standards Virginia SOLs Activities
NSTA 3a
CH. 5 a
Heavy newspaper
Anti-gravity water
Inverse test tube
Boyle’s Law
NSTA 1a, 6a
CH. 5 b
Holes in a bottle demonstration
Sucking water through a straw
Cartesian diver experiment
Absolute zero and NSTA 3a
CH. 5 a
Absolute zero video
temperature
Superfluid video
conversion
Charles’ Law
NSTA 1a, 6a
CH. 5 b
Pingpong ball recovery
Demonstration
Syringe in water bath experiment
Gay-Lussac’s
NSTA 1a, 6a
CH. 5 b
Tire explosion example
Law
Steam engine video
Avogadro’s hypothesis
TED gas property video
Assessment
Activity Sheet
Worksheet
Activity sheet
Homework
Day 6
Combined Gas
Law 1
NSTA 1a, 6a
CH. 5 b
Day 7
Combined Gas
Law 2
Ideal Gas Law 1
Ideal Gas Law2
NSTA 1a, 6a
CH. 5 b
Phet simulation
Activity sheet
NSTA 1a, 6a
NSTA 1a,b,c
CH. 5 b
CH. 5 b
Activity Sheet
Activity sheet
NSTA 1a, 6a
CH. 5 b
Lecture & Notes
Bell jar & vacuum pump
experiment
Lecture & Notes
NSTA 1a, 6a
CH. 5 b
Butane gas experiment
Activity Sheet
NSTA 1a,b,c
2c, 3b, 4b
CH. 5 a, b
Day 8
Day 9
Day 10 Dalton’s Law
of Partial
Pressure 1
Day 11 Dalton’s Law
of Partial
Pressure 2
Day 12 Gas Law Test
Test
Homework
Practice
Problems
Test
Unit Plan Reflection
I believe I have achieved the NSTA standards 1a-c, 2c, 3b, 4b, 6a-b, 7b, 8a through the
unit plan I have created on gas laws, which includes Boyle’s law, Charles’ law, Gay-Lussac’s
law, combined gas law, ideal gas law, and Dalton’s law of partial pressure
The unit plan I have made suited my students’ zone of proximal development. 5-E
learning model is an efficient way to plan and teach lessons. It is so important to engage students
at the beginning of a class period instead of putting the interesting phenomenon in the middle of
a lecture, when students are much less likely to concentrate on what is being taught. Whenever I
perform a demonstration which contradictory to their belief, or when I bring up an interesting
topic they never think of, students are extra focused and excited for my explanation, so that I can
introduce and lecture the new concepts very effectively.
Students need hands-on experience to explore possible answers to the contradictory
engaging demonstrations. I always try to invoke students to think critically and analyze what
they’ve experience. Exploration stage in 5-E model serves this purpose very well. Students also
need to apply their knowledge on experiments after the explanation stage so that the knowledge
would not just be a formula or definition; it would come alive as and be relevant to students’
lives. Experiments are not meant for students to just follow step and record data; they meant to
aid students synthesize knowledge stored in memory and apply them. When I am designing a lab,
I always make sure that the activity sheet would guide students to think critically by asking indepth analysis questions.
During the explanation stage, I always make inclusive Power point slides to show
detailed diagram so that in-depth analysis and explanation is made possible. I lecture new
concepts mostly though Power point slides since they are essential to provide students visual aids:
I would list important points they need to take notes of; I would make it rich in graphic including
pictures, diagrams and animations which is application of concepts in an engaging way; Power
point slides are also a reminder for me to ensure I have conveyed all ideas I am supposed to.
Students find Power point slides helpful, neat and engaging too. I always make sure that my
students can relate the knowledge to something they know of, so that the lesson would not be
abstract and far from reach for them. I use real-life example, simile and experiments to make
knowledge applicable and accessible to them.
I have incorporated multiple types of assessments in my unit plan. The most frequent and
informal way of assessment is checking on everybody’s progress after I have explained a concept
and let them work on a practice problem. I would patrol around the classroom to see if they have
grasped the fundamental skill. I have utilized, collected and graded worksheet, homework,
lab/activity sheet to evaluate their understanding. Homework is great way to have students
practice, check their progress and solidify their newly-learned concepts, which is also a valuable
resource to inform me as to how well students grasp the knowledge. Worksheets are meant to be
finished in class, so that students can have immediate one-on-one assistance from the teacher if
they encounter any question, which is a great way for student-and-teacher interaction. Lab/
activity sheets guide and encourage students’ thinking on top of instructing them as to how to set
up and operate equipment.
Day 1: Property of Gas Pressure
Purpose of Study
Students are going to learn about the characteristics of gas pressure and volume through
teacher’s demonstration and interactive experiments, which knowledge are the foundation for the
further study of gas laws.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
a) pressure, temperature, and volume;
Materials and Resources
Test tubes
Water
Containers
Index cards
Smart board
Notebook
Safety Issues
Safety goggles need to be worn when experimenting.
Procedures:
Engage
1. Prompt students to reason real-life scenarios regarding pressure and volume for example, balloon
would burst at certain altitude. There is about 1,000kg or 2200lbs of air pressure on our body,
which is approximately the same as having a small car pressing down on us. (5 minutes)
Explore (Anti-gravity water experiment)
2. Each student will be asked to submerge a test tube under a water bath, and then pull the test tube
up from the surface of water with the open end down at different heights. (10 minutes)
Explain
3. Students would explain the phenomenon using graphs, diagrams, words, or etc. on a piece of
paper. Teacher would give PPT notes on the property of gas pressure. (20 minutes)
Elaborate (Inverse test tube experiment)
4. Each student will be given an index card to cover a test tube full of water, and then turn the test
tube upside down to observe what would happen. Students would explain the phenomenon using
graphs, diagrams, words, or etc. on a piece of paper. (15 minutes)
Evaluate
5. Teacher would go around and check students’ understanding and ask them to reason the
experimental phenomena.
Day 2: Boyle’s Law
Purpose of Study
Students are going to learn about the Boyle’s Law following the 5-E learning model in a 50minute class. Students will learn pressure and volume are inversely proportional to each other
when temperature and amount of gas is fixed.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Straws
Soda bottles
Fastener nuts
Plastic droppers
Water
Smart board
Activity sheet
Safety Issues
Students cannot suck the water through straw using mouth.
Procedures:
Engage
1. Teacher would perform holes in a bottle demonstration: water would leak through the holes
however, after capping the bottle up, water would stop leaking. (5 minutes)
Explore
2. Student would transfer water using a straw: each student would insert a straw into a tub of water
and put thumb tightly onto the open end of straw, then list the straw up away from the beaker
without loosening up the thumb on the straw. (10 minutes)
Explain
3. Students would explain the phenomenon using graphs, diagrams, words, or etc. on the worksheet.
Teacher would teach the concept of Boyle’s Law. (15 minutes)
Elaborate
4. Students are asked to bring empty plastic bottles if available. Build a Cartesian diver by screwing
a fastener nut onto a plastic dropper, using which to withdraw an appropriate amount of water.
Put the Cartesian diver in a soda bottle with ¾ water and squeeze the Cartesian diver up and
down.
5. Students would explain the phenomenon using graphs, diagrams, words, or etc. on the worksheet.
(20 minutes)
Evaluate
Performance Criteria
Evidence
The student is able to identify and draw The student completes question
the change in gas volume as well as its No.1, 2, and 3 on the activity sheet
pressure.
and provides reasoning.
The student is able to correctly identify The student completes question
the relationship between pressure and
No.1 and No.3 on the activity sheet
volume under constant temperature.
in a reasonable fashion.
The student clearly grasps the concepts The student completes the task
of Boyle’s law and is able to utilize its
“Cartesian diver experiment”
formula from to analyze specific
(question No. 5)
information.
A= completes activity and achieves standard
B= completes activity and nearly attains standard
C= does not complete activity and begins to attain standard
Rating
Activity Sheet
Holes in the bottle:
1. Draw the diagram of the soda bottle, air inside, water and other important facts. What have you
observed? Why does it happen?
Sticky Straw
2. How can you transfer water using a straw without using your mouth?
3. Draw a diagram and try to explain why it would work:
Cartesian diver
Build a Cartesian diver by screwing a fastener nut onto a plastic dropper, using which to withdraw an
appropriate amount of water. Put the Cartesian diver in a soda bottle with water and squeeze the Cartesian
diver up and down.
4. Draw the water line both inside the soda bottle and inside the Cartesian diver before and after you
squeeze the soda bottle in the diagram below:
5. Explain the change in pressure and volume for both the air inside the soda bottle and inside the
Cartesian diver when the bottle is squeezed. Prove your point using appropriate formula.
Day 3: Absolute zero and temperature conversion
Purpose of Study
Students are going to learn about the concepts of Kevin, Fahrenheit, and Celsius temperature
scales as well as their conversion following the 5-E learning model in a 50-minute class.
Students will learn a lot of interesting facts when temperature is near absolute zero and complete
a worksheet on temperature conversion.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
a) pressure, temperature, and volume;
Materials and Resources
Smart board
Activity sheet
Safety Issues
Students would be advised not to practice dry ice or liquid nitrogen without supervision.
Procedures:
Engage
Students would watch a video about super liquid when helium is around absolute zero
temperature. (http://youtu.be/2Z6UJbwxBZI) (5 minutes)
Explore
1. Teacher would prompt students to think about how cold is the coldest temperature and let
students watch a video about absolute zero degree. (http://youtu.be/TNUDBdv3jWI) (10 minutes)
Explain
1. Teacher would teach the concept of absolute zero and temperature conversion using PowerPoint
slides. (15 minutes)
Elaborate
2. Students will complete the temperature conversion worksheet in class. (15 minutes)
Evaluate
A= score 16 points or above on the worksheet (every question worth 1point; 19 points in total)
B= score 12 points or above on the worksheet (every question worth 1point; 19 points in total)
C= score 8 points or above on the worksheet (every question worth 1point; 19 points in total)
D= score 7 points or below on the worksheet (every question worth 1point; 19 points in total)
Temperature Conversion Worksheet
Ko= Co + 273
Fo = 9/5 Co +32 Co = 5/9(Fo-32)
Convert the following to Fahrenheit
1) 10o C ________
2) 30o C ________
3) 40o C ________
4) 37o C ________
5) 0o C ________
Convert the following to Celsius
6) 32o F ________
7) 45o F ________
8) 70o F ________
9) 80o F ________
10) 90o F ________
11) 212o F ________
Convert the following to Kelvin
12) 0o C ________
13) -50o C ________
14) 90o C ________
15) -20o C ________
Convert the following to Celsius
16) 100o K ________
17) 200o K ________
18) 273o K ________
19) 350o K ________
Day 4: Charles’s Law
Purpose of Study
Students are going to learn about Charles’ Law following the 5-E learning model in a 50-minute
class. Students will learn Volume and temperature are inversely proportional to each other when
pressure and amount of gas is fixed.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Syringe
Thermometer
Beaker
Ice
Hot plate
Water
Smart board
Activity sheet
Safety Issues
Students need to wear safety goggles during experiment.
Students need to handle hot plate with care and cannot touch its top surface during experiment.
Procedures:
Engage
1. Teacher will demonstrate how to restore a crushed ping pong ball back to round shape after
putting the ping pong ball in boiling water. (5 minutes)
Explore
2. Students will observe the relationship between temperature and volume: they will intake 15ml of
air through a syringe in room temperature. Students will put the syringe into an ice bath and
withdraw water to the maximum mark reading on the syringe (35ml or 60ml depending on the
size of the syringe.) (10 minutes)
Explain
3. Students would explain the phenomenon on the activity sheet. Teacher would teach the concept
of Charles’s Law using PowerPoint slides. (15 minutes)
Elaborate
4. Students will perform the Charles’ law syringe experiment. (See activity sheet for procedure.)
(20 minutes)
Evaluate
Performance Criteria
Evidence
Rating
The student is able to reason the
The student completes question No.1
relationship between temperature and
on the activity sheet and provides
volume.
reasoning.
The student is able to record data in
The student completes the data
appropriate units and plot them
recording and graphing on the
accordingly.
activity sheet in a reasonable fashion.
The student is able to explain the
The student plausibly completes the
recorded data and plotted graph using
two analysis question s on the activity
Charles’ law and its principle.
sheet.
A= completes activity and achieves standard
B= completes activity and nearly attains standard
C= does not complete activity and begins to attain standard
Charles’ Law Activity Sheet
Ping pond ball recovery:
1. What happened to the crushed pingpong ball? Why did this happen?
Charles’ Law Syringe Experiment
Procedure:
1. Intake 15mL of air using syringe at room temperature.
2. Insert the syringe into the ice water bath and withdraw water to the maximum mark reading
(35mL or 60 mL depending on your syringe size.)
3. Insert a thermometer into the ice water bath. Wait for 2 minutes.
4. Record the volume of water inside the syringe and temperature of water bath in the activity
sheet.
5. Record the temperature of water bath in the activity sheet for every mL change in volume of
water inside the syringe.
6. Plot a graph of volume vs. temperature, and extrapolate (extend) the best fit line to a volume
of zero.
Data:
Total Volume (Volume of water + Volume of Air) = ____________________________
Vwater (mL)
Vair (mL)
T (o C or oF)
T (oK)
Vwater / T (mL/ oK)
Analysis:
1. A direct relationship is one where the dependent variable increases or decreases in the same
direction as the independent variable. For example as obesity increases in a population so does
the incidence of diabetes. An inverse relationship will see the change in the opposite direction to
the independent variable (“as the number of days left in the year decreases, student excitement
increases”). What do we have here?
2. Somewhere you may have heard that the equation for a linear relationship can be described as
y=mx+b. Does your data look like it? Could it be described this way? Explain.
Day 5: Gay-Lussac’s Law
Purpose of Study
Students are going to learn about the Gay-Lussac’s Law following the 5-E learning model in a
50-minute class. Students will learn pressure and temperature are directly proportional to each
other when volume and amount of gas is fixed.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Worksheet
Safety Issues
None
Procedures:
Engage
1. Teacher will invoke students thinking about the relationship between pressure and temperature by
real-life example: tire would be more likely to explode during summer time on highway. (5
minutes)
Explore
2. Teacher will show students a video about how steam engine works and engage students’
discussion. (10 minutes)
(http://youtu.be/73txXT21aZU)
Explain
3. Teacher would teach the concept of Gay-Lussac’s Law using PowerPoint slides, as well as going
over Boyle’s Law and Charles’ Law which have been taught previously. (15 minutes)
Elaborate
4. Students will work on the mixed gas law worksheet, which encompasses Boyle’s Law, Charles’
Law and Gay-Lussac’s Law. The worksheet will be due as homework the next day. (20 minutes)
Evaluate
A= score 18 points or above on the worksheet (every question worth 3point; 21 points in total)
B= score 14 points or above on the worksheet (every question worth 3point; 21 points in total)
C= score 10 points or above on the worksheet (every question worth 3point; 21 points in total)
D= score 9 points or below on the worksheet (every question worth 3point; 21 points in total)
Mixed Gas Law Worksheet
1.0 atm = 101.3 kPa = 760 mmHg
And 0C = 273 K
Change the following units: 359 kPa = _________ atm
6.2 atm = ________ kPa
10C = ________ K
10K = _______ C
1. The gas in a sealed can is at a pressure of 3.00 atm at 25C. A warning on the can tells the
user not to store the can in a place where the temperature will exceed 52C. What would the gas
pressure in the can be at 52C?
2. A sample of hydrogen exerts a pressure of 0.329 atm at 47C. The gas is heated 77C at
constant volume. What will its new pressure be?
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?
6. 5.36 liters of nitrogen gas are at -25C and 733 mm Hg. What would be the volume at 128C
and 733 mm Hg?
7. At constant temperature, 2 L of a gas at 4 atm of pressure is expanded to 6 L. What is the new
pressure? (Do this one conceptually and not algebraically.)
Day 6-7: Combined Gas Law
Purpose of Study
Students are going to learn about the combined gas law in two 50-minute class. Students will
learn the combined gas law concepts from Power point slides and work on practice problems in
the first 50-minute class period; students will spend the next 50-minute class period complete a
PhET simulation lab.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Computers
Smart board
Activity sheets
Safety Issues
None
Procedures:
First 50-minute class
1. Teacher will teach the combined gas law concepts using Power point slides.
2. Students will work on practice problems.
Second 50-minute class
3.
Students will complete a PhET simulation lab and its worksheet as shown below.
PhET Gas Law Simulation Worksheet
(The worksheet is cited from
http://phet.colorado.edu/new/simulations/sims.php?sim=Gas_Properties)
Part 1: Play
Procedure:
1. Pump the handle once. Watch the temperature and pressure gauge. See how long it takes for the
values to stabilize. Record the values in Table 1 on the next page.
2. Using the little person pushing on the wall, decrease the volume of the box in about half. Describe
what happens to:
Temperature:
Pressure:
3. Using the little person pushing on the wall, make the volume as small as possible and watch for at least
60 seconds. Thoroughly describe what happens over the course of the full minute. Be sure to address the
following in your answer:
a. What happens to the container and the little man pushing on the container?
b. What happens to temperature and pressure?
c. Describe the particle speeds of both the heavy and light species.
4. Hit the “Reset” button. Give the pump a push with the heavy species. Wait for the values to stabilize
and record the results in table 1 on the next page.
Are these values the exact same as the first time you did it? __________ Why or why not?
5. There is a box in the lower right corner entitled “Gas in Pump”. Select the “light species”. You will
notice that the pump turns red. Give the pump a press. Wait for the values to stabilize and record the
results in table 1 on the next page.
6. In the box entitled “Heat Control”, grab the arrow and move it to add. What happens?
7. Using the “Heat Control”, grab the arrow and move it to “remove.” What happens?
8. Feel free to play with the simulator. Try the “Pause” and “Step” buttons at the bottom. Try sliding the
top of the container. Take about 3-5 minutes to play with the different options.
Table 1: Playing with the simulation program
After pumping the After pumping the After cutting the
Reset: Constant
“heavy” handle
“heavy” handle
volume in about
volume 1 pump of
once (1st time)
once
half
heavy species
Temperature (K)
Pressure (atm)
Added 1
pump of light
species
Number of Heavy
Species
Number of Light
Species
Part Two: Boyle’s Law
Purpose: To see how pressure and volume are related to each other (keeping everything else constant).
Procedure:
1. Hit the reset button.
2. In the upper left corner under “Constant Parameters”, select “Temperature”. This will make sure that
temperature will not change significantly.
3. We will need a way to measure the volume. Hit the button “Measurement Tools”. Select the “Ruler”
box. A ruler should appear at the top of the screen. The ruler can be moved so you can measure the size
of the box. This will make a good way of measuring the volume.
4. To see how the relationship between pressure and volume works, temperature and number of moles
must be constant. The temperature can be held constant by selecting it in the corner.
5. Take 8 separate measurements over a large range of numbers without exploding the container.
Table 2: Volume and Pressure of a gas with temperature constant at_______ and Particles constant at
_________
Volume (nm)
Pressure (atm)
Volume x
Pressure (nm x
atm)
Questions:
1. What is the independent variable?
2. What is the dependent variable?
3. What 2 factors are being held constant?
4. What does the mathematical relationship indicate?
Part 3. Charles’ Law
Purpose: to determine the relationship between volume and temperature (with everything else constant).
Procedure: You get to design how to test the purpose. Write down the settings you put the simulator to.
Please note:
if you want to hold pressure constant, the container must have something in it first. Add
particles, then hold pressure constant. If you hold pressure constant before adding particles in the
container (P = 0 atm), the program will attempt the impossible, by trying to hold the pressure at 0 atm.
1. What is the independent variable?
2. What is the dependent variable?
3. What 2 factors are being held constant?
Make a data table to collect at least 8 pieces of data over a large range. Be sure the data table has the
proper components (title, units, gridlines, etc).
Table 3: ___________________________________________________________________
Make a graph of the Charles’ Law relationship. Be sure your graph has all of the proper components.
7. Describe the relationship of Charles’ Law. Be sure to include the variables and constants in your
answer.
Day 8-9: Ideal Gas Law
Purpose of Study
Students are going to learn about the ideal gas law following the 5-E learning model in two 50minute classes. Students will elaborate their learning on experiments such as boil water at room
temperature.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Smart board
Bell jar and vacuum pump set
Activity sheets
Safety Issues
Students do not need boiling water in this experiment. The water at room temperature will boil in bell jar.
Procedures:
Engage
1. Students will watch a TED video about property of gas (5 minutes)
(http://youtu.be/BY9VGS2eXas)
Explore
2. Demonstrate that one mole gas of all kinds occupies 22.4 liter of volume under standard
temperature and pressure through dividing molecular mass by density, which is based on
Avogadro’s hypothesis. (10 minutes)
Explain
3. Teacher will teach the concept of ideal gas law using Power point slides. (35 minutes)
Elaborate
4. Students will perform the bell jar and vacuum pump set experiment. They will measure the mass
of air, inflate a piece of marshmallow and boil a cup of water at room temperature. (50 minutes)
Evaluate
Performance Criteria
The student is able to understand that
pulling air out would decrease the amount
of air inside the jar and decrease it mass.
The student clearly grasps the relationship
between amount of gas and pressure.
Evidence
Rating
The student completes question No.1-16
in Part A on the activity sheet and
provides reasoning.
The student completes question No.2-4
in Part B and No.2-7 in Part C on the
activity sheet in a reasonable fashion.
The student is able to analyze all variable
in ideal gas law and apply its principle.
The student completes question No. 8 in
Part C on the activity sheet in a
reasonable fashion.
A= completes activity and achieves standard
B= completes activity and nearly attains standard
C= does not complete activity and begins to attain standard
Bell Jar Vacuum Pump Activity Sheet
(This activity sheet is cited from
www.juniata.edu/services/.../MS.../Bell%20Jar%20Vacuum%20Pump.doc)
Setup: The diagram below shows how the bell jar vacuum should be setup.
Figure 1 – Bell jar vacuum pump setup.
1. The O ring, part (C), should already be installed on the bottom plate, part (B).
2. The bell jar, part (A), fits over the smaller diameter portion of the bottom plate with the
rim in contact with the O ring.
3. One fitting of part (D) will connect with the top of the bell jar, part (A). Only a slight
turn, approximately one-third of a gentle turn, is all that is needed to make a secure
connection. DO NOT OVER TIGHTEN!!
4. One of the small arms of the T in part (E) connects to the syringe, part (F). DO NOT
OVER TIGHTEN, only a slight turn is necessary. The other small arm of part (E)
connects to the unconnected fitting of part (D). Only a partial turn is needed, DO NOT
OVER TIGHTEN! The remaining connector of part (E) will be left unconnected. Note:
part (D) and (E) may already be connected to one another.
Procedure
Part A: The Phantom Mass
In this section you will attempt to find the mass of a known gas mixture, air.
1. Study the apparatus. The check valve will easily allow air to flow in the direction shown
by the arrows, but not in the other direction. What is inside the bell jar now? (Hint:
“Nothing” is not correct.)___________________________________________________
2. Have a partner push down on the bell jar to make certain that the bell jar is pressing
against the O ring. While your partner is doing this, pull the piston of the syringe out to
the 60 cc mark. DO NOT pull the piston the whole way out.
3. Where does the air come from that fills the syringe? _____________________________
4. Let go of the piston, and watch what happens. Now quickly push the piston all the way
back into the syringe. Listen for the sound of moving air.
5. Where did the air go that was in the syringe? ___________________________________
6. Describe the amount of force that was required to pull out the piston.
_______________________________________________________________________
7. What kind or kinds of forces resisted you as you pulled out the piston?
_______________________________________________________________________
8. Repeat these steps five times:
1. Pull the piston out to the 60 cc mark
2. Let go of the piston and see what happens
3. Push the piston all the way back in
9. As you followed the steps in #8, what happened to the amount of force required?
_______________________________________________________________________
10. Explain why the amount of force changed in this manner.
_______________________________________________________________________
11. Pull the piston of the syringe out to the 60 cc mark and push it all the way back in. Repeat
this 24 times. You should notice that there is no air movement by the end of this process.
What is in the bell jar now? _______________________________________________
12. Place the bell jar apparatus on a balance. Disconnect part (D) from (E). You should
weigh the bell jar (A), bottom plate (B), O ring (C), and hose (D). Record the mass in the
given data table (page 4).
13. Loosen the connection between hose (D) and the bell jar, remove the hose, and then
reconnect it. Did you hear the movement of air? What was the air doing?
_______________________________________________________________________
14. Again place the bell jar, with hose (D), bottom plate, and O ring on the balance. Make
certain that hose (D) is not touching anything. Record the mass in the data table.
Data Table/ Calculations:
Step
MASS
(0.00g)
12
14
Difference in mass between
steps 12 and 14
Questions:
15. What does the difference in mass represent?
16. Do you think the bell jar was really empty when you weighed it in step 12?
Part B: Marshmallow under Pressure
1. Place the marshmallow inside the bell jar. Reassemble bell jar as previously did. Begin to
pump the piston. What happens to the marshmallow?
________________________________________________________________________
2. Why did the marshmallow change in the way that it did?
________________________________________________________________________
3. Loosen the connection between hose D and the bell jar until you hear the movement of
air. What happens to be marshmallow?
________________________________________________________________________
4. Why did this change occur?
________________________________________________________________________
Part C: Liquid in a Vacuum
1. Imagine some water from the hot water tap that has just been poured into a cup. Why is
the water not boiling now?
________________________________________________________________________
2. Think about the boiling process. The water becomes a gas (steam) bubbles that take up
much more room that made them. Do you thing that the presence of atmospheric helps
the boiling process, or makes it more difficult?
________________________________________________________________________
________________________________________________________________________
3. Can you predict what would happen if we put a container of hot tap water into the bell jar
and pump out the air?
________________________________________________________________________
4. Fill a small beaker with hot tap water. Take its temperature using a thermometer and
record its value below:
________________________________________________________________________
5. Place the beaker inside the bell jar. Reassemble bell jar as previously did. Begin to pump
the piston. What happens?
________________________________________________________________________
6. What do you think has happened to the temperature of the water?
________________________________________________________________________
7. Keep pumping until there is no further effect. Then slowly loosen the connection between
hose (D) and the bell jar. Now open the bell jar and record the temperature of the water.
What has happened?
________________________________________________________________________
8. Explain this experiment using ideal gas law:
PV=nRT
How does P, V, n, R, T react in this experiment? What variable has changed and how has
it change? What variables have stayed about the same?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Day 10-11: Dalton’s Law of Partial Pressure
Purpose of Study
Students are going to learn about Dalton’s law of partial pressure following in two 50-minute
class through lecture and experiment. Students will learn that each kind of gas has partial
pressure, which would add up to the total pressure.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
b) partial pressure and gas laws;
Materials and Resources
Thermometer
Butane lighters with wheels taken off
Graduated cylinders
Water
Smart board
Containers
Activity sheet
Safety Issues
Safety goggles need to be worn at all times during experiment.
Procedures:
First 50-minute class
5. Teacher will teach the Dalton’s law of partial pressure using Power point slides.
6. Students will work on practice problems.
Second 50-minute class
7.
Students will perform Dalton’s law of partial pressure lab and complete its activity sheet as
shown below.
Dalton’s Law of Partial Pressure Lab
PRE-LAB DISCUSSION: A mole of any pure gas at STP has a volume of 22.4 liters. The
weight of that gas in grams is equal to the molecular mass of the gas in atomic mass units. If the
volume, mass, temperature and pressure of a gas is known, then using the combined gas law, its
volume can be mathematically converted to a volume at STP. Then, the mass of 22.4 liters can
be determined. Thus its molecular mass can been determined experimentally.
When gas is collected by water displacement, Dalton's law of partial pressures can be used to
factor out the water vapor.
OBJECTIVE: To experimentally determine the molecular mass of butane.
CHEMICALS/EQUIPMENT: butane lighter, balance, 100 ml graduated cylinder, tub [bucket,
dishpan etc, thermometer glass plate.
PROCEDURE:
1.Determine and record the exact mass of the butane lighter [estimate to the 100th of a gram].
2.Fill the tub or other large container with water.
3.Fill the 100 ml graduated cylinder completely with water and using your hand, invert it into the
tub without permitting any air bubbles in it.
4.Make sure that the lighter is turned to its highest gas flow. Hold the butane lighter under the
mouth of the 100 ml graduated cylinder, press the release lever, being careful that all of the gas
flows into the 100 ml graduated cylinder. Hold the 100 ml graduated cylinder so that the100 ml
mark is exactly even with the water level in the tub. Fill the 100 ml graduated cylinder to the 100
ml mark that you made on the 100 ml graduated cylinder.
5.Determine and record the temperature of the water in the tub and the barometric pressure of the
lab.
6.Thoroughly dry the butane lighter and determine and record its exact mass.
DATA
Initial mass of lighter..............................................................
____________________ g
Final mass of lighter..............................................................
____________________ g
Mass of butane collected.........................................................
____________________ g
volume of butane collected....................................................
____________________ ml
Temperature ......................................................................... ____________________ °C
lab pressure .......................................................................... ___________________ mmHg
water vapor pressure at this temperature...............................
____________________ torr
partial pressure of butane........................................................____________________ torr
CALCULATIONS:
1. Using Dalton's law of partial pressures, enter the pressure of water vapor that corresponds to
the lab temperature in the data table. Then subtract this from the lab pressure to find the partial
pressure of butane gas.
2. Convert the lab temperature from Celsius to Kelvin.
3. Using the combined gas law formula, calculate the volume of butane at STP. Record your
answer.
4. Determine what mass of this gas would produce 22,400 ml at STP. Record your answer.
5. Butane has the formula C4H10. Calculate its molecular mass from this formula. Record your
answer.
6. Calculate your percentage of error.
THINKING SCIENTIFICALLY
1. What could you have done to have more accurate results?
2. Write a balanced equation for the reaction of butane with oxygen.
3. How much butane is contained in a new lighter? [read the label]
4. If all the butane in the lighter is reacted with air:
A. What volume of air would be needed for this reaction? [Hint-air is only 1/5 oxygen]
B. What would be the total volume of the gases produced by this reaction? [Hint-H2O and CO2
are the gases produced]
Day 12: Gas Law Test
Purpose of Study
Students are going to be assessed regarding their understanding on all gas laws they have
studied.
SOLs
CH.5 The student will investigate and understand that the phases of matter are explained by
kinetic theory and forces of attraction between particles. Key concepts include
a) pressure, temperature, and volume;
b) partial pressure and gas laws;
Materials and Resources
Test paper
Safety Issues
None
Procedures:
Students will complete the gas property test in a 50-minute class.
Gas Property Test
1. For a gas, which two variables are inversely proportional to each other (if all other conditions
remain constant)?
A. P, T
B. P, V
C. V, T
D. n, V
E. n, P
2. All of the following statements concerning a sample of oxygen gas at 1.00 atm pressure are true
except
A. The molecules are in constant rapid random motion.
B. The pressure exerted by gaseous oxygen is due to the impact of the molecules with the walls of
the container.
C. The average kinetic energy of the gaseous oxygen is proportional to the absolute temperature of
the gas.
D. The oxygen gas pressure is greater than the pressure created by the same amount of hydrogen gas.
E. The volume occupied by the oxygen molecules is negligible compared with the size of the
container.
3.
A given mass of gas in a rigid container is heated from 400 K to 1200 K. Which of the following
responses best describes what will happen to the pressure of the gas?
A. The pressure will remain the same.
B. The pressure will decrease by a factor of three.
C. The pressure will increase by a factor of three.
D. The pressure will increase by a factor less than three.
E. The pressure will increase by a factor greater than three.
4. a. What is the volume of 1 mole of any gas at STP? __________________
b. What is STP? Provide an answer using at least two different units of pressure and
complete sentences.
_______________________________________________________________________
5. If the temperature of a 2.40 L sample of gas is changed from 30.0 °C to 20.0 °C while the pressure is
held constant, what is the final volume of the sample?
6. At a temperature of -33.3°C, a sample of gas exerts a pressure of 53.3 kPa. If the volume remains
constant, at what temperature will the pressure reach 133 kPa?
7.
If the volume of a sample of gas at 120 °F is changed from 3.40 L to 2.10 L and the pressure changes
from 754 mm Hg to 544 mm Hg, what is the new temperature of the gas?
8. What volume is occupied by 5.03 g of O2 at 28°C and a pressure of 0.998atm?
9. At what temperature in °F would 2.10 moles of N2 gas have a pressure of 1.25 atm and in a 25.0 L
tank?
10. Calculate the pressure in a 212 Liter tank containing 3.4 moles of argon gas at 25°C?
11. A container holds three different gases (N2, O2, and CO2) at a total pressure of 857 mm Hg. The
partial pressure of nitrogen is 561 mm Hg. The partial pressure of oxygen is 249 mm Hg. What is the
partial pressure of the carbon dioxide?