Question

Acid rains are produced by:

• A. excess $NO_2$ and $SO_2$ from burning fossil fuels
• B. excess production of $NH_3$ by industry and coal gas
• C. excess release of carbon monoxide by incomplete combustion
• D. excess formation of $CO_2$ by combustion and animal respiration.

Answer 1

Answer: (A)

When fossil fuel burnt in automobile engines different oxides like $NO, NO_2, SO_2, SO_3$ are produced. In the presence of moisture these oxides convert in the acids. These acids come down from the atmosphere in the form of rain, called acid rain.
$S \left(from fossil fuel\right) + O_2 \to SO_2$
$SO_2 + O_3\to SO_3 + O_2$
$SO_2 + H_2O_2\to H_2SO_4$
$SO_3 + H_2O\to H_2SO_4$
$2NO_2 + H2O \to HNO_3+HNO_2$