APES Unit 7: Photochemical Smog and
Acid Rain Notes
acid deposition - ANS - occurs when nitrogen oxides and sulfur oxides are released into
the atmosphere and combine with atmospheric oxygen and water
- these form the secondary pollutants nitric acid and sulfuric acid
\basic formation of ozone - ANS - in the absence of VOCs, ozone with form during the
daylight hours
\breakdown of ozone - ANS - after sunset, the ozone will break down
\effects of acid deposition - ANS - lowering the pH of lake water
- decreasing species diversity of aquatic organisms
- mobilizing metals that are found in soils and releasing them into surface waters
- damaging statues, monuments, and buildings
\formation of acid deposition - ANS - the primary pollutants sulfur dioxide and nitrogen
oxides are precursors to acid deposition
- after transformation to the secondary pollutants - sulfuric and nitric acid - dissociation
occurs in the presence of water
- the resulting ions - hydrogen, sulfate, and nitrate - cause the adverse ecosystem effects
of acid deposition
\formation of photochemical smog - ANS - in the presence of VOCs, ozone will form
during sunlight hours
- the VOCs combine with nitrogen oxides to form photochemical oxidants, which reduce
the amount of ozone that will break down later and contribute to prolonged periods of
photochemical smog
\inversion layer - ANS - the layer of warm air that traps emissions in a thermal inversion
\thermal inversions - ANS - a situation in which a relatively warm layer of air at
mid-altitude covers a layer of cold, dense air below
\
Acid Rain Notes
acid deposition - ANS - occurs when nitrogen oxides and sulfur oxides are released into
the atmosphere and combine with atmospheric oxygen and water
- these form the secondary pollutants nitric acid and sulfuric acid
\basic formation of ozone - ANS - in the absence of VOCs, ozone with form during the
daylight hours
\breakdown of ozone - ANS - after sunset, the ozone will break down
\effects of acid deposition - ANS - lowering the pH of lake water
- decreasing species diversity of aquatic organisms
- mobilizing metals that are found in soils and releasing them into surface waters
- damaging statues, monuments, and buildings
\formation of acid deposition - ANS - the primary pollutants sulfur dioxide and nitrogen
oxides are precursors to acid deposition
- after transformation to the secondary pollutants - sulfuric and nitric acid - dissociation
occurs in the presence of water
- the resulting ions - hydrogen, sulfate, and nitrate - cause the adverse ecosystem effects
of acid deposition
\formation of photochemical smog - ANS - in the presence of VOCs, ozone will form
during sunlight hours
- the VOCs combine with nitrogen oxides to form photochemical oxidants, which reduce
the amount of ozone that will break down later and contribute to prolonged periods of
photochemical smog
\inversion layer - ANS - the layer of warm air that traps emissions in a thermal inversion
\thermal inversions - ANS - a situation in which a relatively warm layer of air at
mid-altitude covers a layer of cold, dense air below
\
