Name________________________________ Period_____ Date______________
Greenhouse Effect Laboratory Investigation
Questions
What is the greenhouse effect? How does the amount of greenhouse gases in the atmosphere affect the
temperature of the earth?
Background
Carbon dioxide, CO2, is a colorless gas that is present in our atmosphere due to natural and
anthropogenic (man-made) sources. Carbon dioxide, water vapor, ozone, methane, nitrous oxide, and
chlorofluorocarbons (CFCs) absorb and trap heat energy and thus act like a global heat blanket. Because
of this, they are referred to as greenhouse gases. In this investigation, we will focus on CO2. CO2 is
naturally present in the earth’s atmosphere, and a certain amount of the greenhouse effect is both
normal and desirable. However, the widespread combustion of fossil fuels and increased deforestation
has increased the level of CO2 in our atmosphere. In the past century, the amount of CO2 in our
atmosphere has increased more than 20%. There is evidence indicating increased levels of CO2 are
enhancing the greenhouse effect, and many scientists are concerned that this will result in a significant
increase in the earth’s average temperature. In this lab, we will try to model how an increased level of
CO2 increases the average temperature of the earth. It is worth noting that many of other greenhouse
gases have been increasing in our atmosphere as well.
Procedure
1. Obtain two plastic soda bottles and caps, a sheet of black construction paper, scissors, clear
tape, a ruler, three plastic backed thermometers, three 6” pieces of string, a supoort stand and
a light source.
2. Tie a 6” piece of string to the hole at the top of one of the thermometers. Repeat with the other
bottle.
3. Cut a 6” x 6” piece of black construction paper to fit over one-half of the outside surface of one
of the bottles.
4. Tape the construction paper on the outside of both bottles.
5. Place a thermometer inside the neck of one of the bottles. Allow the string to hang over the
neck of the bottles and screw on the cap. The thermometer should be suspended in the bottle.
Repeat with the other bottle.
6. Place approximately 30g of sodium bicarbonate (baking soda) into one of the plastic bottles.
7. Cut half of the “bulb” off of a pipet. Place the pipet into a one-hole rubber stopper. Make sure
that air cannot leak out.
8. Place the neck of a balloon over the bulb of the pipet. Make sure that air cannot leak out.
9. Pour approximately 100 mL of vinegar into the plastic bottle and quickly place the one-hole
stopper into the mouth of the plastic bottle. The balloon will inflate with carbon dioxide gas.
10. Place both bottles 20 centimeters in front of the light source. Be certain that they will both
receive the same amount and intensity of light. Turn on the light.
11. Record the temperature of both bottles at 1 minute intervals for ten minutes. Turn light off.
12. Record the temperature of both bottles at 1 minute intervals for ten minutes.
Data Collection
Time (min)
0
1
2
3
4
5
6
7
8
9
10
Turn Light Off
1
2
3
4
5
6
7
8
9
10
Bottle filled with air
Bottle filled with air
and CO2