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Grade 12Physical Chemistry

Why does the rain water normally have a pH of about 5.6? When does it become acid rain?

Profile image of Raghav
12 Years agoGrade 12
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2 Answers

Profile image of Suraj Prasad
11 Years ago
Pure water has a pH of 7.0 (neutral); however, natural, unpolluted rainwater actually has a pH of about 5.6 (acidic).[Recall that pH is a measure of the hydrogen ion (H+) concentration.] The acidity of rainwater comes from the natural presence of three substances (CO2, NO, and SO2) found in the troposphere (the lowest layer of the atmosphere).
Profile image of Karan Dholakia
8 Years ago
) found in the troposphere (the lowest layer of the atmosphere).2NO, and SO2,Pure water has a pH of 7.0 (neutral); however, natural, unpolluted rainwater actually has a pH of about 5.6 (acidic).[Recall that pH is a measure of the hydrogen ion (H+) concentration.] The acidity of rainwater comes from the natural presence of three substances (CO