Atmospheric Chemistry and Water Quality Lecture Notes

Flashcards covering atmospheric layers, acid rain, the greenhouse effect, photochemical smog, ozone depletion, and water quality parameters based on the lecture transcript.

Troposphere

The atmospheric layer that contains $99\%$ of all atmospheric gases.

Stratosphere

The atmospheric layer where the ozone layer is located.

High energy UV radiation

The type of radiation essential for the formation of the ozone canopy.

Carbon dioxide ($CO_2$)

The acidic gas dissolved in normal rainwater that contributes to a minimum pH of $5.6$.

Acid Rain precursors

Sulfur ($S$) and Nitrogen ($N$) are the two main elements responsible for the formation of acid rain.

Nitric oxide ($NO$)

The nitrogen oxide produced in the atmosphere during lightning strikes or within engines under high pressure and temperature.

Sulfuric acid ($H_2SO_4$)

A strong acid produced when $SO_2$ reacts with rainwater and oxygen ($O_2$).

Heavy metal leaching

The process caused by acid rain where ions such as $Al^{3+}$, $Cd^{2+}$, $Cr^{3+}$, and $Hg^{2+}$ are removed from soil and enter water bodies.

Calcium carbonate ($CaCO_3$)

A substance (limestone) used to remove $SO_2$ from power plants and the chemical in marble statues that reacts with acid rain.

Natural Greenhouse Effect

The natural process that helps maintain the Earth's average temperature at approximately $15^\circ\text{C}$.

Infrared (IR) radiation

The specific type of radiation absorbed by greenhouse gases in the atmosphere.

Methane ($CH_4$)

An organic greenhouse gas significantly added to the atmosphere through rice cultivation.

Nitrous oxide ($N_2O$)

A greenhouse gas released into the atmosphere due to the use of nitrogen-based fertilizers.

Halogenated hydrocarbons

A group of gases (including CFC, HFC, and HCFC) that can be thousands of times more potent as greenhouse gases than $CO_2$.

Photochemical Smog

An atmospheric condition requiring temperatures above $15^\circ\text{C}$, characterized by a brown color due to $NO_2$.

PAN

The abbreviation for Peroxyacetyl nitrate, a primary secondary pollutant found in photochemical smog.

Catalytic converters

Devices installed in vehicles to reduce emissions of $NO$ and hydrocarbons by converting $NO$ into $N_2$ and $O_2$.

Chlorine free radicals

The specific reactive units derived from CFC molecules that destroy ozone.

HCFC

Hydrochlorofluorocarbons; internal $C-H$ bonds allow these to be destroyed in the lower atmosphere, making them safer for the ozone layer than CFCs.

HFC

An alternative gas that does not damage the ozone layer at all but still functions as a greenhouse gas.

Water Hardness

A condition caused primarily by the presence of $Mg^{2+}$ and $Ca^{2+}$ cations in water.

Sodium carbonate ($Na_2CO_3$)

The chemical added to water to remove permanent hardness.

Eutrophication

A process where excessive nutrient Enrichment leads to algal blooms, covering the water surface and depleting dissolved oxygen ($O_2$).

Phosphate ions ($PO_4^{3-}$)

The ions that typically act as the limiting factor in the process of eutrophication.

Hydrogen sulfide ($H_2S$)

A foul-smelling gas produced by bacteria at the bottom of reservoirs under anaerobic conditions.