Why does rain water normally have a pH of about 5.6? When does it become acid rain ?
Rain -water normally has a pH of 5.6 due to the formation of carbon dioxide present in the atmosphere.
When the pH of the rain drops below 5.6, it becomes acidic. Actually, the acidity of rain water is increased due to the large quantity of SO2 and oxides of nitrogen present in the air.
What are the consequences of green house effect?
Or
What is the effect on the global warming due to the green house effect?