GenESS lab Properties of Air (1)

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Name:________________________________________________________ pd:______ date:_______________________________
Exploring the Properties of Air Lab
Part 1: Measuring a parcel of air.
1.Using a balloon and a scale, determine the mass of a volume of air in grams.
a.) Find the mass of the balloon empty
b.) Blow the balloon up and tie it. Now find the mass of the balloon filled with air.
c.) Subtract (Find the Difference) between the two masses.
2. Using a string and ruler, estimate the diameter of your balloon in centimeters.
Data table
1
Mass of the balloon
(uninflated) (g)
2
Mass of the balloon (inflated)
(g)
3
Mass of air inside the balloon (g)
(row 2 – row 1)
4
Estimated diameter of balloon
(cm)
Total mass of air contained in this
5 column of atmosphere (row 3 x
row 5)
1
Did you know……
Anything with mass has weight, and we know air has mass because (for example) we
can feel it when the wind blows. The total weight of the atmosphere exerts a pressure
of about 15 pounds per square inch at sea level. You don't notice this weight, however,
because you are used to it. You have equal amounts of air pressure pushing on your
body from all sides. Gravity and Air Pressure work together, Air at sea level is being
compressed by all of the air above it, weighing it down and increasing its density. The
higher you go in the atmosphere (altitude) air pressure deceases.
Discussion questions:
1. If air has mass and pressure, describe why you are not currently getting crushed by
it! USE COMPLETE SENTENCES.
2. Would you expect the mass of the air column to be greater or less on top of Mt.
McKinley (6,190 m above sea level), as compared to Death Valley (86 m below sea
level)? Why?
2
Part 2: What is the relationship between air
pressure and temperature?
1. Place 20 ml of water in a can.
2. Heat the can on a hot plate until you see steam coming out of the top. In the left box, make a model of
what you observe. (be sure to label the movement of water and atmospheric gases in and/or out of the
can.)
3. Use beaker tongs to carefully turn the can upside down into a container of water.
4.
Record your results as a labelled model in the right box.
Use arrows to indicate how water moves.
Analysis:
1. After you heat the can and flip it upside down into the water, the air pressure inside the
can is _____________________ and the air pressure outside is __________________________.
2. Why does water flow into the can from the bowl of water?
_______________________________________________________________________________________________
_______________________________________________________________________________________________
_______________________________________________________________________________________________.
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3. Just like the water, air will flow from areas of __________________ pressure to areas of
_______________ pressure.
4. The can on the hot plate is an example of what type of thermal energy?
___________________________
5. The water inside the can boiling due to the heat plate is an example of what type of
thermal energy?
___________________________
6. If you were to hold your hands near the hot plate to feel the heat coming off of it, this would represent what type
of thermal energy?
__________________________________
4
Name:______________________________________________________ pd:________ date:___________________________________________
Part 3: Is there water in the air?
1. Half fill a glass with water. Record the temperature of the room and the water.
2. Add ice cubes until the glass is full. Record the temperature of the water at 10 second
intervals.
3. Observe the outside of the glass.
4. Note the time and the temperature at which condensation occur on the outside of the glass.
5. Once condensation has occurred the data collection can stop.
Data table: Indoor room temp = _______oC temp water = _______oC
Time
s
0
Temp
o
C
Change?
no / yes
Time
s
90
Temp
o
C
Change?
no / yes
Time
s
200
Temp
o
C
Change?
no / yes
Time
s
290
10
100
210
300
20
110
220
310
30
120
230
320
40
130
240
330
50
160
250
340
60
170
260
350
70
180
270
360
80
190
280
370
Temp
o
C
Change?
no / yes
4. Repeat the investigation outside. Record the temperature of the water and the air outdoors.
Data table Outdoor temp = _______ oC
Time
s
0
Temp
oC
Change?
no / yes
Time
s
90
Temp
oC
Change?
no / yes
temp water = _______oC
Time
s
200
Temp
oC
Change?
no / yes
Time
s
290
10
100
210
300
20
110
220
310
30
120
230
320
40
130
240
330
50
160
250
340
60
170
260
350
70
180
270
360
80
190
280
370
Temp
oC
Change?
no / yes
5
Analysis
1. Compare and contrast Describe how the atmosphere outside of the glass changed to produce condensation.
__________________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________________
2. Relate your experiences of wet grass in the early morning to the lab conditions that allowed the atmosphere to reach
its “dew point” (What happened to the air to form condensation?)
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