Question

Where is acid rain a problem in North America?

Answer 1

Mostly the northeastern US states, as the SO2 (sulphur dioxide) produced by the "clean" coal industry lowers the pH of rainwater.

Explanation:

Acid rain is becoming far less common as we move to cleaner forms of energy, but unfortunately areas like the northeastern USA are still producing/using coal that contributes to low pH rain. Again though, acid rain is a very minor problem compared to how bad it used it be before the Clean Air Act was passed in 1970 and reinforced with stricter regulations in 1990, resulting in significant reductions in SO2 emissions.