Acid Rain and Seed Germination
Purpose:
Does the pH of acid rain affect the germination of seeds?
Hypothesis:
Write a testable hypothesis.
Materials:
Radish seeds
Vinegar and water (simulated acid rain)
Graduated cylinders
pH indicator
cotton batten/balls
filter paper
Experimental Design:
1. Label four different beakers with masking tape, and prepare the following solutions for each:
a. Pure acid rain (pour vinegar in the beaker to a depth of 2 cm).
b. Solution with pH of 3.5 (mix vinegar with water until desired pH is reached, pour depth of
2 cm into a beaker)
c. Solution with pH of 5.0 (mix vinegar with water until desired pH is reached, pour depth of
2 cm into a beaker
d. Tap water to a depth of 2 cm
2. Test the pH of each beaker and ensure you record the pH of each beaker. Label each beaker.
3. Place 40 radish seeds in each of the beakers and allow them to soak for 24 hours. Make
observations of the seeds in each of the beakers.
4. Prepare 4 other small beakers by placing a layer of cotton batten in the bottom, and cover the
cotton with a piece of filter paper.
5. Pour the contents of the beaker with tap water and the seeds into one of the prepared beakers and
label. Repeat for each of the other 3 beakers. Cover the tops with the lid or a piece of paper and
leave them.
6. Count the number of seeds that have germinated in each of the beakers after 24 hours.
7. Count the number of seeds that have germinated in each of the beakers after 48 hours.
Observations:
Record observations for each of the beakers after soaking the seeds, germination after 24 hours, and
germination after 48 hours in a chart/table. Create a graph to display this information graphically.
Discussion:
1. How does the pH affect the germination of seeds? Write a paragraph to describe if the evidence
supports your hypothesis or not.
2. If a farmer planted 20 000 seeds, how many would germinate? Explain how this would affect
his/her expenses.
3. Research to answer: How are different crops affected by varying levels (pH) of acid rain? Ensure
you reference your sources.
Report:
1. Introduction: Write a paragraph (1/4 of a page) briefly describing the causes and formation of
acid rain. All sources must be cited. In your final sentence state your hypothesis.
2. Results and Observations: Present all of your observations in a chart, and in a line, pie, or bar
graph.
3. Discussion: Answer the discussion questions in paragraph form. Include a conclusion statement.