What is the pH of rain in your area? Students take pH measurements for rain in their neighborhood and compare it with other students' findings. This activity is best when conducted over several weeks during a rainy time of year.
pH test strips
1 plastic 1-oz. cup for each student
What To Do
DISTRIBUTE one cup and five test strips per student. Students take cups home. Each time it rains, students COLLECT rain water in their cups. They TEST the water with one strip of pH paper, and bring the pH paper to class.
DRAW a map of the neighborhood on a wall chart. Students PIN their paper on the map in the location where they collected the rain water. On successive rainy days, student PIN additional papers to the right of previous ones.
As a class, DISCUSS the pH of water in the neighborhood. Did the pH change over time? Was the pH different in different areas? What are some possible reasons for this?
What's Happening? Find out more from our acid rain hotlist.
Challenge: Test the pH of a river. Does the pH vary for different sections of the river? Are there other water sources you can test in your city? Be sure to share your results in our pH Exchange.