Cloud in a Bottle Instructions
This activity will help with understanding of adiabatic temperature changes as well as how clouds are formed.
Materials: Matches, Water, clear 2-liter bottle with cap
1. Put a little bit of water in the bottle and cap it. You do not need a lot, just enough to fill it up a fingerâ€™s width or two.
2. Take a guess at what the humidity is with the cap on the bottle? (3 points)
3. Squeeze the bottle.
a. What happens to the pressure inside the bottle when you squeeze it? (3 points)
b. What happens to the temperature inside the bottle when you squeeze it? (3 points)
c. What happens to the pressure when you release the bottle? (3 points)
d. What happens to the temperature when you release the bottle? (3 points)
4. Uncap the bottle and light a match. Hold the bottle at an angle while holding the lighted tip of the match inside the bottle. Count 5 seconds then cap the bottle quickly so that the smoke does not escape. Swirl the smoke and water around for 2 seconds (best if you tip the whole bottle upside down).
5. Squeeze the bottle now filled with water and smoke and release.
a. What happens when you released the bottle? (3 points)
b. How is the cloud being formed in the bottle? (5 points)
c. What is a condensation nucleus? (3 points)
d. Briefly describe adiabatic heating and cooling. (5 points)
After activity questions:
1. In step #2 of the procedure, you squeezed the bottle changing the temperature and pressure.
a. How did this change the humidity in the bottle? (3 points)
b. When you released the bottle, how did that change the humidity in the bottle? (3 points)
2. How is this activity similar to how clouds are formed? (5 points)