Question

What is acid rain? What are two strong acids present in acid rain?

Answer 1

Acid rain

• When the atmospheric pollutants like the oxides of sulfur and nitrogen react with rainwater and come down in the form of rain, then this rain is known as acid rain.
• Acid rain or acid deposition is a broad term that includes any form of precipitation with two main acid components such as sulfuric acid$\left({\mathrm{H}}_2{\mathrm{SO}}_4\right)$ and nitric acid$\left({\mathrm{HNO}}_3\right)$ that fall to the ground from the atmosphere in wet or dry forms. This can include rain, snow, fog, hail, or even dust that is acidic.

Chemical Reactions

• The emission of sulfur dioxide and nitrogen oxide is responsible for acid rain.
• Sulfur dioxide combines with water and air to form sulphuric acid.
• $$\begin{gathered} {\mathrm{SO}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{H}}_2{\mathrm{SO}}_3 \\ (\mathrm{Sulfur}\mathrm{dioxide})\left(\mathrm{Water}\right)(\mathrm{Sulphuric}\mathrm{Acid}) \end{gathered}$$
• Nitrogen dioxide reacts with water to form nitric acid nitrous acid.
• $$\begin{gathered} 2{\mathrm{NO}}_2+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{HNO}}_2+{\mathrm{HNO}}_3 \\ (\mathrm{Nitrogen}\mathrm{dioxide})\left(\mathrm{water}\right)(\mathrm{Nitrous}\mathrm{Acid})(\mathrm{Nitric}\mathrm{acid}) \end{gathered}$$