1. Condensation, Clouds, Precipitation Investigation 6
Water in the Air
Condensation, Clouds, Precipitation
Investigation 6
TG- P

2. Pressure / Temperature Demonstration
What happens to the temperature of a gas if you squeeze it into a smaller volume?
Pressure/Temperature Demonstration worksheet
TG- P. 209
Student Lab Notebook- P.37
Teacher Answer Master- P.400

3. Soda Bottle Demo #1 Resting temperature
Apply pressure to the bottle and hold it
Observe the temperature
Release the pressure and observe the temperature
TG- P. 209
Student Lab Notebook- P.37
Teacher Answer Master- P.400

4. Soda Bottle Demo #2 Starting temperature
Pump the cap 40 times or more as you watch the temperature
Observe the pressure
Release the pressure and observe the temperature
TG- P. 209
Student Lab Notebook- P.37
Teacher Answer Master- P.400

5. Results  (added air molecules)   Squeezed by Hand Bottle
Soda-bottle Pump Bottle
Volume 
 (added air molecules)
Pressure 
Temperature
TG- P. 209
Student Lab Notebook- P.37
Teacher Answer Master- P.400

6. What happened… When we released the pressure Temperature decreased
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

7. Questions
Answer questions 2, 3 and 4 on the Pressure/Temperature Demonstration worksheet
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

8. Question 2 Answer V  = MM  = P  = T 
Decreasing the volume causes the molecules to move faster with the greater pressure, increasing the temperature
V  = MM  = P  = T 
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

9. Question 3 Answer V  = MM  = P  = T 
Squeezed the sides of the bottle = decreased the space = pushed down on the plunger. The number of air molecules stayed the same in a smaller space = increase pressure, increased temperature
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400
V  = MM  = P  = T 

10. Question 4 Answer V  = MM  = P  = T 
Temperature must go up in the syringe because the pressure goes up
V  = MM  = P  = T 
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

11. Summarize Gas molecules are forced closer Force smaller volume
More collision occur
Increase in temperature and pressure
Force smaller volume
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

12. Summarize Gas molecules spread out Less collision occur
Decrease in temperature and pressure
Increase the volume

13. Cloud Formation Have you seen any clouds lately?
What did they look like?
Where are clouds?
Are they always in the same place?
What is a cloud?
What is it made of?
Where do clouds come from?
How do you think they form?
TG- P. 211

14. 2 Types of Clouds
Clouds appear as one of these 2 basic types…
Stratiform– clouds that are flat and layered. These form when weather is stable. They are the result of a large, moist air mass being lifted.
Cumuliform—puffy, fast-moving, and rapidly growing clouds.

15. Clouds are classified by height

16. Cloud Word Orgins Cumulus- Latin – “heap” Stratus – Latin – “layer”
Nimbus – Latin – “rain-bearing”
Cirro- “high”
Alto- “middle”

17. High Cirrus Cirrocumulus Cirrostratus
Clouds forming above 5000 meters have cirro- prefix and since the temperatures are so cold at such high elevations, these clouds are primarily composed of ice crystals.
These clouds are thin and wispy, blown by high winds into long streamers. They are typically thin and white in appearance, but can appear in a magnificent array of colors when the sun is low on the horizon.
Cirrus
Cirrocumulus
Cirrostratus

18. Middle
Clouds that form between m are given names that begin with the alto- prefix.
Nimbostratus
Altostratus
Altocumulus

19. Low Low level clouds form below 2000 meters. (no special prefix)
-Stratus
-Stratocumulus
-Cumulus
-Cumulonimbus

21. Cloud in a Bottle?
Using a 2-liter soda bottle, containing 25 mL of water
Water vapor into the air?
Shaking the bottle
Warming the water
TG- P. 211

22. Shake, shake, shake
Have we formed a cloud yet?
NOT YET
TG- P. 211

23. Cloud recipe Saturate the air with water vapor Then Shake the bottle
Warm the bottle by holding it in your hands
Increase the pressure to increase the temperature
Then
Release the pressure on the bottom to decrease the temperature (to get the water vapor to condense - dew point)
TG- P. 212

24. Did it Work? NOT YET! There is a piece missing
There is nothing for the water droplets to form on!!
TG- P. 212

25. What’s Happening?
When you let it expand the water condenses on the smoke particles forming a cloud.
When the bottle is compressed the air gets hotter so the water evaporates.
You start off with some  water in the bottle and some smoke.

26. Condensation Nucleus
Clouds are composed of tiny droplets of condense liquid water
Water vapor is condensing on the particles of smoke and the plastic of the bottle
The particle on which water vapor condenses in the air to form a cloud
TG- P. 212

27. Is This How Real Clouds Form?
The process is very similar to how clouds from on a sunny day. Warm moist air rises, and as it rises there is less air above it so the pressure reduces.

28. In Real Clouds
What would be the condensation nuclei in the outside air?
Dust
Smog
Air pollution
Smoke
Salt
Chemicals
TG- P. 212

29. How do Clouds Form?

30. Precipitation Water that falls from the sky Kinds of precipitation
Rain
Snow
Sleet
Hail
TG- P. 213

31. Raindrops and Cloud Droplets
Measure the average diameters
Comparison of size - page 80 in the Resource Book
TG- P. 213
Student Resource Book P. 80

32. Measuring Precipitation
Most important weather factors monitored
Measured with a rain gauge
TG- P. 213
Student Resource Book P. 80

33. Fog Forming on Land

34. Don’t forget to use the helpful website links on Science page for additional information