Rationale
Phytoplankton have a key role in the production of oxygen and the resulting use of carbon dioxide in the atmosphere during photosynthesis. They alter the chemical characteristics of the water due to their biological processes. Because of the short season of light availability in Antarctica, the phytoplankton are profoundly more productive in each 24 hour period than are general oceanic phytoplankton. Therefore, the waters of Antarctica have an important role as a significant carbon dioxide sink. This may prove to be extremely important in light of our greenhouse gases problems.

Grade Level/Discipline
9-12, but may be adapted to advanced 8th grade classes

Objectives

• Students will observe the effect of the gases resulting from a burned fossil fuel on the heat absorption of air.
• Students will determine the ability of phytoplankton to remove greenhouse gases from the atmosphere

National Standards
Teaching Standards: A, B, D, E; Content Standards: A, C, F;
Program Standards: B; System Standards: A, B, F

Teacher Preparation for Activity
Materials
For each group:

• 2 large jars with screw lids that have holes for probe-ware or thermometer
  - pickle jars from the cafeteria work well

  2 temperature probes or thermometers

  2 CO2 probes or limewater Calcium oxide (CaO)

  2 candles

  matches or lighter

  1 sunlamp

1. Slowly add calcium oxide (CaO),one teaspoon at a time, to a large Pyrex beaker of water. If you add too rapidly, the whole container could boil over, so do a small bit at a time. It will be hot, so handle with insulated gloves or beaker tongs.
2. Continue adding CaO to the solution until no more will dissolve.
3. Make up solution right before use and keep tightly closed because it will react with the CO2 from the air, turning it prematurely cloudy.

1. Quickly add 20ml limewater to the bottom of the jars after the candle has been burned and place the lid or cork back
2. Shake or agitate the bottle so that the CO2 in the bottle will mix with the limewater.

1. See Figure I for jar setup
2. Place one sunlamp fairly close to and the same distance from the two jars.

1. Divide the students into lab groups or set up the activity as a demonstration.
2. Hand out Data Collection Sheet SM - 3
3. Inquire of the students the purpose of the second jar (control). Why is it a control?
4. Ask the students what the purpose of the sunlamp is this time (heat).
5. Assign one student in each group to be a time-keeper so that accurate time intervals can show the increase and eventual decrease in temperature in a controlled manner.

1. Ask the students to post their data and average each groups findings.
2. Ask what function the burning candle served in the activity. (fossil fuel burning)
3. How did the burned hydrocarbon affect the heat retention of the atmosphere?
4. How can this increase in carbon dioxide affect our global weather patterns? (warming trend)

Exchange (Students Draw Conclusions)

Evaluation (Assessing Student Performance)

Authors
Besse Dawson
Pearland High School
3775 S. Main Street
Pearland, Texas 77581

Background
To show the effects of burning fossil fuels on the atmosphere, a simple activity involving a candle burned inside a large, clear jar with temperature and CO2 probes inserted Another large pickle jar with the same probes filled with regular atmospheric air serves as a control. A sunlamp is directed on both jars and both CO2 and temperature are recorded for 30-45 minutes. The lamp is shut off and the CO2 and temperature are again recorded for 30-45 minutes.

If a CO2 probe is not available, using the limewater will show the presence of CO2 by turning cloudy. The limewater absorbs 25-35% of its weight in carbon dioxide, forming calcium carbonate which is a white precipitate. Be aware of the safety concerns: Strongly corrosive and irritating to skin, mucous membranes and eyes. Ingestion can cause severe damage to the G.I. tract.
Activity III should be used after this.

Resources
Consultants: Dr. Dave Karl Principal Investigator/Research Mentor University of Hawaii dkarl@soest.hawaii.edu

Chris Carillo University of Hawaii

Dr. Nancy Bell University of Texas Medical Branch

Dr. Virginia Gordy Pearland High School

Biological Oceanographic Processes 3rd Edition; T.R. Parsons, M. Takashi, B. Hargrave; Butterworth-Heineman, 1995.

Student Reproducible Masters

Carbon Dioxide The Heat is On!
Group Names ______________________________________________________
Procedure:

1. Set up two large jar as shown in the picture on accompanying page.
2. Light the candle in the second one and let it burn for five minutes.
3. Blow out the candle and quickly tightly shut the lid to trap the smoke.
4. Shine a sunlamp on both the jars so that both are equally heated by the lamp.
5. Record the temperature and carbon dioxide values every 5 minutes for a total time of 30 minutes.
6. Turn off the lamp and remove it from the area close to the jars.
7. Record the temperature every 5 minutes for the next 30 minutes.

Time         5        10        15     20      25      30
             T  CD    T  CD    T  CD   T  CD   T  CD   T   CD
Heating
Jar # 1
(plain jar)


Heating
Jar # 2
(candle)


Cooling Jar
# 1


Cooling Jar
# 2

Analysis
1. What happened to the temperatures of the plain jar versus the candle jar.
2. What is the impact of the candles burning on the heat retention?

CONCLUSION:
1. What could cause similar products being put in the atmosphere?
2. What impact could placing these products in our atmosphere have on it?

Figure 1

We look forward to hearing from you! Please review this activity.