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

2. Remember… Wet spot felt cold
Energy transfers from hand to water by conduction
Because of the energy transfer, our skin felt cooler.
The powerpoint follows the Teacher Guide starting with slide 12. Slides 2-11 are excellent slides leading into slide 12.
Increased energy  water molecules move faster
Faster moving molecules evaporated

3. Big Question
What happens to the temperature of a gas when it is squeezed into a smaller volume?

4. When water is changed from a gas to a liquid
Condensation
When water is changed from a gas to a liquid

5. Heat Transfer & Condensation
Is heat transfer involved?
Yes
Water Vapor
Very Cold Surface
Energy
Reduces kinetic energy in water molecules
Condenses into liquid water

6. Water Vapor Water Vapor Transfer energy to surroundings
Vapor condenses
Forms liquid water
Water Vapor
Energy
Very Cold Surface
Energy transfers to cold surface
Drops of liquid water form there

7. Dew Condensation on a cold glass
Dew is droplets of water seen on plants and other surfaces, usually in the morning

8. Dew forms? How does dew form? Surfaces cool
Water vapor condense into droplets
Cool leaves
Water Vapor
Energy

9. Dew Point
The temperature at which air is saturated, causing water vapor to change from a gas to a liquid
Cool leaves
Water Vapor
Energy

10. Dew Point Not the same everywhere
Need to calculate the dew point for a particular location

11. Depends on… The amount of water vapor in the air
Lots of water vapor = high dew point (higher temperature)
Little water vapor = low dew point (lower temperature)

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

13. 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

14. 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

15. 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

16. What happened… When we released the pressure
Temperature decreased
With partners/group, discuss and respond to questions 2-4 on lab worksheet.
Will review in 5 minutes.
TG- P. 210
Student Lab Notebook- P.37
Teacher Answer Master- P.400

17. 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

18. 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 

19. 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

20. 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

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

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

23. Cloud in a Bottle Watch cloud in a bottle video with Mr. Yorke.
TG- P. 211

24. Condensation Nuclei Flip ?s
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

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

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

27. Raindrops and Cloud Droplets
Scientists have measure the average diameter (pg. 80)
Precipitation is one of the most important factors that meteorologists monitor.
Measure rain in rain gauge.
Snow is melted and weighed to report inches or centimeters.
TG- P. 213
Student Resource Book P. 80

28. Summary Five minutes on the timer
Write everything you know or have learned about condensation.

29. Reading Two pages of notes on “Observing Clouds”
Notes are free style, but must demonstrate organization
Must include a blurb regarding Luke Howard
Respond to Think Questions thoroughly, cleverly, and scientifically
Notes be spread over 2 pages (no squishy)