Lab 5: All About Air Pressure
Summary and Learning Objectives
Students select a storm from the HURDAT database and create its track in the easy-to-use online tool, Google Maps. The visualization they produce details the location and intensity of their storm through time. Afterwards, students access an online mapping tool to examine the locations and life cycles of hundreds of Atlantic storms.
After completing this investigation, students will be able to:
- Students will conduct simple lab experiments to gain first-hand experience with the effects of air pressure.
- Students will work effectively in groups to conduct experiments and analyze the results.
Context for Use
This lab has students working in groups to conduct simple laboratory experiments. It was designed for high school Earth Science students but is also applicable to introductory level students in college Geoscience courses. One 50-60 minute class period is required for the activity. There are six stations that the groups will rotate between so, depending on your class length, each station should take between 8 and 10 minutes. The lab requires common lab equipment like Bunsen burners and having it set up in a space designed for laboratory work is recommended.
Activity Overview and Teaching Materials
This lab requires a fair amount of pre-class setup. You will need to put together the different exercises at different stations. There are 6 stations in the lab so you will need to divide your class into 6 teams. (Ideally of 3-5 students each, but class size may not allow it.) The teams will move from station to station, completing the exercises cooperatively as they go.
There are printable Station Cards (Acrobat (PDF) 74kB Sep19 07) of materials and instructions that you can place at each station to help lead students through the exercises. The directions are also on the activity sheet (Acrobat (PDF) 175kB Sep27 07) that you will hand out at the beginning of the lab. There is also a
(The activity sheet is also available in a word processing format (Microsoft Word 2007 (.docx) 452kB Aug7 18).)
Station 1: Collapsing pop can
Station Card 1 (Acrobat (PDF) 66kB Sep18 07)
- Aluminum pop can
- Bunsen burner or small propane torch and striker
- Claw holder (the kind that can be attached to ring stands)
- Bucket of cold water
- Oven mitt (or equivalent) and safety glasses
- Metric rulers
- Measure the height and diameter of the can. Make a note of this information on the activity sheet.
- Put a small amount of water in the bottom of the can. Just enough to cover the bottom.
- Wearing goggles and an oven mitt, hold the can in the claw over the heat source. Do so until there is a good chimney of steam coming out the opening in the can. This might take a couple of minutes.
- Quickly invert the can into the bucket of cold water and watch the results.
- Complete the questions on the activity sheet.
Station 2: Balloon in a Bell Jar
Station Card 2 (Acrobat (PDF) 66kB Sep18 07)
- Bell jar
- Vacuum pump
- 2 Small balloons, partially inflated to the same size.
- Masking tape
- Tape one of the balloons to the top inside of the bell jar. Leave the other on the outside for comparison. (This step won't be necessary for subsequent groups.)
- Connect the vacuum pump and evacuate some air out of the bell jar.
- Complete questions on activity sheet.
- Release the vacuum so that the apparatus is ready for the next group.
Station 3: Ruler and Newspaper
Station Card 3 (Acrobat (PDF) 66kB Sep19 07)
- Sheets of newspaper
- Wooden rulers or flat pieces of wood (that you don't mind breaking!)
- Part A
- Place the ruler on a bench top with about a quarter of its length hanging over the edge.
- Make sure the area around you is clear of people, then give the overhanging piece a quick "karate chop" with your hand.
- Retrieve the ruler and replace it in the same position on the bench.
- Lay one full sheet of newspaper over the part of the ruler that is on the bench.
- Repeat your chop to the overhanging part of the ruler.
- Record your observations and answer the questions on the activity sheet.
Station 4: Egg in a Bottle
Station Card 4 (Acrobat (PDF) 66kB Sep18 07)
- Hard boiled eggs (with shells removed).
- A bottle or flask with an opening that is just small enough to prevent the egg from entering the bottle. Each group should have their own bottle as one of the students will have to put it to their mouth.
- Part A
- Drop a burning match into the bottom of the bottle.
- After a few seconds, place the egg onto the mouth of the bottle.
- Compete the relevant areas on the activity sheet.Part B
- Now that the egg is in the bottle, turn the bottle upside down so that the egg is resting in the neck of the bottle.
- Tip back your head, place your mouth over the bottle opening and blow vigorously into the bottle.
- Quickly remove your lips from the bottle hold it over the bench.
- Complete this section of the activity sheet.
- Wash the bottle with soap and hot water so that it's ready for the next class.
Station 5: Soda Bottle and Ping Pong Ball
- Soda bottle (Sobe 20oz bottles work well)
- 1 Ping pong ball
- Graduated cylinder
- Metric ruler
- Beaker to collect water
- A barometer (reading in kPa)
- Obtain a reading of atmospheric pressure from the barometer at the station. Record this on the activity sheet.
- Fill the bottle all the way to the top with water.
- Push the ping pong ball onto the top to squeeze out a small amount of water.
- Now, pour off about one third of the water in the bottle into the graduated cylinder and record this amount as V0 (pronounced "vee sub zero") on the activity sheet.
- Hold the ping pong ball on top of the bottle and invert it over the beaker. Hold the ball loosely against the opening so that some water is allowed to leak out into the beaker. Don't jiggle or rotate the ball during this process.
- Eventually, enough water will leak out that the pressure on both sides of the ball will be the same and you can take your hand away and the ball will stay. Add the water that leaked out to the graduated cylinder and record this total amount as V1 (pronounced "vee sub one") on the activity sheet.
- Measure the distance from the mouth of the bottle to the top of the water it encloses and record this distance as D on the activity sheet.
- Complete the calculations called for on your activity sheet to determine the atmospheric pressure in your classroom. Compare your calculated value to the reading you took off the barometer and answer the questions on the activity sheet.
Station 6: News Article Review
Station Card 6 (Acrobat (PDF) 66kB Sep18 07)
Copies of these news articles:
- Why the Earth's air is really an ocean
- Flatter oceans may have caused 1920s sea rise
- Forecasters Mark 15th Anniversary Of Hurricane Andrew
- Study Eyes Stratosphere, Weather
- Everyone in the group should pick an article to read. Everyone should take a different one unless there are more group members than articles.
- Spend the first few minutes reading your article and then write a paragraph summary (on your activity sheet) of what the main points of the article were and what you learned from it.
- When everyone is finished, each person should spend 1 minute telling the rest of the group about the article and fielding any questions their group-mates might have about the material.
- Keep an eye on the time so that everyone gets a chance to share what they learned!
- In your own words, write a couple of sentences based on the summary that your group-mates give of their articles.
- Leave the articles for the other groups to use when you move on to your next lab station.
- Activity Sheet (PDF (Acrobat (PDF) 175kB Sep27 07) and Word (Microsoft Word 2007 (.docx) 452kB Aug7 18))
- All Station Cards (Acrobat (PDF) 74kB Sep19 07)
- Station 1 Card (Acrobat (PDF) 66kB Sep18 07)
- Station 2 Card (Acrobat (PDF) 66kB Sep18 07)
- Station 3 Card (Acrobat (PDF) 66kB Sep19 07)
- Station 4 Card (Acrobat (PDF) 66kB Sep18 07)
- Station 5 Card (Acrobat (PDF) 70kB Sep18 07)
- Station 6 Card (Acrobat (PDF) 66kB Sep18 07)
- Zip File (Zip Archive 1.3MB Aug7 18) of all Printable Materials
Teaching Notes and Tips
The instructor will need to be moving around the room troubleshooting issues with equipment, although most of the materials in this lab are very simple. The instructor should also be aware of how the groups are working together.
Below you will find specific notes or suggestions for each of the stations in this lab.
If you have the resources, you can set up 2 or 3 Bunsen burners or torches at this station so that every student on each team has the opportunity to do the activity themselves.
Be sure to talk to the students about safety regarding the burners and torches and that they wear the hand and eye protection during the activity.
This can also be done with a hot plate if the other heat sources aren't possible in your classroom.
You'll need to provide your students with the altitude at your location or allow them to look it up for themselves so that they can do the calculations.
If your school does not have a bell jar and vacuum pump, you can substitute the following activity which uses an empty wine bottle and a hand pump available for less than $20.
Alternate Activity for Station 2: Wine Bottle and a Balloon (Acrobat (PDF) 55kB Sep27 07)
Alternate Station Card for Station 2 (Acrobat (PDF) 56kB Sep18 07)
Flying rulers do pose a safety hazard! Make sure that this activity is taking place in such a way as to minimize its impact on the rest of the class.
If you have enough rulers or pieces of wood, more than one student on each team can do this activity in succession.
Be sure that each group has their own bottle, as one of the students will have to put it to their mouth.
You'll probably want to have one hard boiled egg per group with extras just in case.
The amount of water that leaks out is small and it doesn't take long to reach the point where the internal pressure and the external pressure are balanced. It should be possible for most or all of the team members to do this activity themselves in the time allotted.
Remind your students not to let bubbles of air into the bottle when they are letting the water leak out. This will introduce an error into their calculations.
If you have large group sizes, you may need to provide more than one copy of each article so that everyone has one to read.
Collect the activity sheets and grade on effort and accuracy. You may also wish to have a part of the grade for the lab (10-15% or so) be based on how well the teams work together. If you choose this route, be sure to check out the Starting Point module on Cooperative Learning for pointers.
State and National Science Teaching Standards
Understanding air pressure: This overview from the National Weather Service's JetStream gives a very nice overview of what is known about air pressure.
If you are unfamiliar with having students working in groups, take a look at the Starting Point website on Cooperative Learning.
Atmospheric Pressure and Wind Visualizations: These visualizations can help you make the connection between these hands-on activities and global phenomena that involve wind and atmospheric pressure.