Environmental Chemistry - Atmospheric Pollution

Tropospheric pollution involves gaseous pollutants like oxides of sulfur ($SO_x$), nitrogen ($NO_x$), and carbon ($CO, CO_2$), as well as particulate matter.

Acid Rain is formed when $SO_2$ and $NO_x$ react with water vapor and oxygen in the atmosphere to form $H_2SO_4$ and $HNO_3$. Rain is considered 'acidic' when its $pH$ falls below $5.6$.

Classical Smog occurs in cool humid climates and is a mixture of smoke, fog, and sulfur dioxide ($SO_2$). It is chemically a reducing mixture.

Photochemical Smog occurs in warm, dry, and sunny climates. It results from the action of sunlight on unsaturated hydrocarbons and nitrogen oxides produced by automobiles and factories. It contains $O_3$, $NO$, and Acrolein/PAN ($CH_3COONO_2$).

The Greenhouse Effect is the warming of the Earth's surface due to the trapping of infrared radiation by gases like $CO_2$, $CH_4$, $O_3$, $CFCs$, and water vapor.

Ozone Layer Depletion occurs in the stratosphere primarily due to the release of Chlorofluorocarbons ($CFCs$). These compounds break down under $UV$ radiation to release chlorine free radicals ($Cl^\bullet$).

Carbon Monoxide ($CO$) poisoning occurs because $CO$ binds with hemoglobin to form carboxyhemoglobin, which is about $300$ times more stable than the oxyhemoglobin complex, reducing oxygen transport in the blood.