Name the chemical substances which cause acid rain and describe where they come from; both natural and man made sources.  Write word  and chemical equations for these reactions of acids.  

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jerichorayel eNotes educator| Certified Educator

Acid rain is the phenomenon where the precipitation is have become unusually acidic. The effects of acid rain can affect the natural environment thus harmful to humans and other organisms. Acid rain is cause by the emission of sulfur dioxide (`SO_2` ) and nitrogen oxides (`NO_x` ) from either natural (volcanic eruption, lightning, etc...) or man-made (factories, electricity generators, motors, etc...) sources. Carbon which is abundant in the Earth's atmosphere can also change the acidity of the rain. The chemical reaction of acid rain phenomena can be summarized as:

From `CO_2` :

`H_2O + CO_2 <=> H_2CO_3 (weak acid)`

`H_2CO_3 + H_2O <=> H_3O^+ + HCO_3^-`


From `SO_2` **:

`SO_2 + OH (f r) + O_2 -> SO_3 + HO_2 (f r)`

`SO_3 (g) + H_2O (l) -> H_2SO_4 (aq)`


From NO_2 :

`NO_2 + OH (f r) -> H_NO_3 (aq)`


`(f r)` -> free radical

**There are many other equations for the chemical reaction of acid rain products. Consider the references cited.