Beacon Lesson Plan Library

The Acid Rain Test

Daric White

Description

This is a research project to increase students' abilities to conduct experiments, interpret data and discuss results in a scientific paper.

Objectives

The student organizes information using appropriate systems.

The student knows that the world ecosystems are shaped by physical factors that limit their productivity.

The student knows the ways in which humans today are placing their environmental support systems at risk (e.g., rapid human population growth, environmental degradation, and resource depletion).

The student knows that investigations are conducted to explore new phenomena, to check on previous results, to test how well a theory predicts, and to compare different theories.

Materials

-Seeds (bean seeds work well)
-Trays that are at least 1foot by 1foot by 3 inches deep.
-Potting soil
-Nitric or sulfuric acid
-Spray bottles
-Electronic stirrer
-Stirring magnet
-Labels
-Water proof pen
-Computer with word processor and graphics package
-pH paper or meter
-Rulers with centimeters

Preparations

1. Prepare several liters of acid rain by adding nitric or sulfuric acid to water drop wise until desired pH is reached. (usually pH of 3 or 4 will work)
2. Pour acid rain solution into spray bottle and label it low pH.
3. Pour water (tap water will work) into spray bottle and label it water.
4. Make sure all other materials are obtained.
5. Prior to beginning experiment, make sure students understand the concepts of acid rain and pH.

Procedures

Background: Students should have prior understanding of how acid rain is formed and its effects. Students should also understand how the pH scale works.

1. Students should work in pairs.

2. Students obtain two planting trays.

3. Each tray will be filled with potting soil within a half-inch of the top.

4. Students obtain 20 bean seeds: 10 seeds from the ones soaking in water and 10 seeds from the ones soaking in the low pH conditions.

5. Students label one tray low pH and one tray water.

6. Students plant the low pH tray with the 10 seeds that have been soaking in the low pH solution and the water tray with the 10 seeds that have been soaking in water. Seeds should be planted in two rows at equal distances apart.

7. Students label each seed with plastic labels and water proof ink. Label seeds 1 through 10 in each tray.

8. Everyday for one week, students will spray each tray thoroughly. The water tray will be sprayed with the spray bottle labeled water and the low pH tray with the spray bottle labeled low pH.

9. After one week of spraying everyday, students will switch to spraying every other day for a period of 3 to 5 weeks.

10. During the experiment, students should:
A. Keep track of which seeds germinate for each tray.
B. How many germinate in each tray.
C. Measure plant size in centimeters twice a week after germination.
D. Measure leaf size twice a week.
E. Make observations as to leaf shape, color of plant or any other irregularities that might occur.
F. Record measurements and observations in a notebook.

11. In a class discussion ask students to discuss and comment on the following questions:
--Can you review the procedure of the experiment?
--What did you predict would happen?
--What did happen? Did it happen to all of the experiments?
--What physical factor influenced the results?
--Why?
--Does this knowledge have a practical application?

12. Students will write a scientific paper consisting of an Introduction, Methods and Materials, Results and Discussion of results. Allow students time to research which should be included as well as a listing of the sources in correct bibliographical format.

Assessments

Scientific Paper rubric to be used in assessing the students' work:
1. Introduction -10 points-to include the purpose of the experiment and the hypothesis
2. Methods-10 points-to include materials and procedures
3. Results-30 points-to include data generated over the 7 weeks including measurements, and observations in annecdotal format
4. Discussion -40 points-to include original hypothesis, change, speculation, and research as well as the role humans have in the outcome
5. References -10 points-to be included in bibliographic format (at least 3)

Extensions

Any type of plants can be used.
Different pH's can also be used.
Comparative studies can be done on plant type or pH ranges etc
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