What is acid rain? How is acid rain caused? What are the harmful effects of acid rain?
When the concentration of rain has a pH value less than 5.5 is said to be acid rain. The number of harmful gases like oxide of sulphur and nitrogen in the environment reacts with rain water - it results in the formation of sulfuric acid, and nitric acid which causes the decreasing of pH value and cause acid rain.
The harmful effects of acid rain are: