Science Buddies: "Ask an Expert"

My child is doing a science project on the impact of acid rain and pollution on plant growth.

For the acid rain portion it was suggested she use water with higher ph levels. Is that a correct assumption?

For the pollution portion, what type of water or what should she add to the water to create polluted water.

If you have any suggestions regarding this project we would appreciate hearing from you.

Thank you

That is a correct assumption. You could add dirt to the water, or collect some rain water before it goes into the gutter.

Hi,

To add on to what probiotics said, acid rain actually has a lower pH than regular rain or pure water. Pure water's pH is 7.0, normal rain's pH is between 5.0-5.5, while acid rain's pH is around 4.0. To achieve a similar effect as acid rain, you could collect rainwater, especially if you live in a city, and test its pH with pH strips (these are relatively inexpensive and can be ordered online) to confirm that it's around the pH of acid rain. Another alternative would be to add some lemon juice or vinegar to water and test its pH to confirm it's around 4.0, but make sure you record the volumes of acidic substance and water used to achieve the desired pH so this result can be replicated later. Even though the types of acid in acid rain are sulfuric and nitric acid, you should get a similar result with lemon juice or vinegar.

For pollution, the most accurate way to simulate polluted water would likely be to collect water from a local river, lake, or stream that is known to be polluted. However, you could also try adding soil to water, like what probiotics mentioned.

Hope this helped,
Allison