In this activity the students will create an Air Mass Generator to investigate how an air mass forms in unstable air and then stable air.
Click Here to see a drawing of our Air Mass Generator. As you read the directions you may want to go back and forth between the two pages.
Materials:
- Plastic Cylinder: We made ours out of a plastic tube found at Home Depot.
- Two centigrade thermometers: Tape one at the top of the cylinder and the other one at the bottom. It must not be submerged in the water though. (You will have to move this around to get it in the correct location for your materials.
- Clear plastic dish with a cover: We found a plastic dish that held our cylinder perfectly. The dish must hold 2.5 cm of very hot water. It also needs to have a lid so the smoke will not leak out.
- Plastic Tubing: This will get inserted into the plastic cylinder. Our teacher heated a nail and then put it in the plastic. It made a hole large enough for the tubing. Our tubing was aquarium tubing.
- Funnel: Attach the tub end of the funnel to the end of the plastic tubing. The diameter of the tubing will depend on the diameter of the end of the funnel. It must fit tight.
- Cotton Rope: You will need 15 cm of cotton rope or you can use a gas lantern mantle. This is the smoke generator. Our teacher used a gas lighter to set the rope on fire then we blew it out as she held it. This created the smoke we needed to put in the funnel.
- Hot Tape Water: You will need 2.5 cm of hot tape water. Boiling water may melt the plastic. The hot water is used to show unstable air.
- Crushed Ice: you will need enough crushed ice to fill the plastic cylinder. The crushed ice is used to show stable air.
Safety Note: In this experiment you will be using fire and heat. Let your teacher help you or an adult. You may burn yourself.
Procedure:
- Build your Air Mass Generator. It may not look exactly like ours though. We had to experiment with the design to get it to work. You may have to do the same thing.
- The first lesson will be about an unstable air mass. Place 2.5 cm of very hot water in the bottom of the plastic cylinder.
- Light the end of the cotton rope and blow it out. The cotton rope should now be smoking.
- Hole the smoking cotton rope under the funnel. The funnel will trap the smoke and it will rise through the tubing.
- The warm air from the hot water will cause the smoke to rise up the cylinder. Read the temperature at the bottom and top of the cylinder. You will notice that the smoke begins to drop as it reaches the top. Does the temperature have anything to do with this?
- Next empty out the hot water and let the smoke clear from the tubing and funnel.
- Fill the cup at the bottom with crushed ice.
- Let your teacher light another piece of cotton rope and blow it out as before. Trap the smoke under the funnel again. Notice what happens to the smoke this time. What is the temperature of both thermometers?
