NY 12866 Rain and snow are naturally somewhat acidic because of carbon dioxide in the atmosphere. As rain ralls through the air, carbonic acid is formed, resulting in a typical pH of clean natural rain of approximately 5.6.
Atmospheric pollutants can lower the pH even more.
The effect of acid rain on lakes and streams depends on their natural buffering capacity. This actvity sheet is available as a PDF file. You will need to download Acrobat Reader to be able to read this file. Halstead, Judith A. Rain, Lakes, and Streams - Investigating Acidity and Buffering Capacity in the Environment J. Chem. All rights reserved.