8.5 ACID DEPOSITION
INTRODUCTION:
- DEFINED  Acid deposition (a secondary pollutant) is the process by which acid-forming pollutants are deposited on
Earth’s surface.
- acid deposition can be _________ (e.g. rain) or ________ (particle or gas)
- The most prevalent form of acid deposition is acid ___________.
- Acid rain can be considered to be a major _______________ environmental problem.
- Other acid deposition forms include __________, ___________ and __________.
*CAUSES OF ACID RAIN:
- The major pollutants that cause acid rain are sulfur dioxide, SO2 and nitrogen oxides, NO and NO2. *These oxides react
with water to form the strong acids: ______________ and _________________ acids.
- ____ industrialization/economic development = ____ emissions of sulfur/nitrogen oxides = ____ acid rain
-Note that sources of these oxides may also be _________________ in origin.
Main Sources of sulfur and nitrogen oxides:
NATURAL OCCURANCES
HUMAN ACTIVITY
- volcanic eruptions
- combustion of ______________ fuels (e.g. coal, oil) containing high levels of
_______________ impurities
- decomposition of vegetation
- the internal combustion engine(NOx)
- e.g. car and jet engines
- emissions from ________________ (SO2)
- refining of copper, nickel and other metal ores that contain sulfur
*ADVERSE EFFECTS/ IMPACTS OF ACID RAIN / ACID DEPOSITION:
- acidification of lakes and river via precipitation and leaching of minerals from soil
- deforestation
- uptake of toxic minerals/metals from soil/water by plants and marine-life
- resulting negative impact on fishing industry (disappearance of fish species such as Atlantic Salmon and Brown Trout)
- negative impacts on people’s health
- corrosion effects on marble, limestone, metal buildings, bridges and vehicles
FORMATION OF ACID RAIN
1. FROM CO2(g) [*Rainwater is naturally acidic (pH  5.6). Acid rain has pH < 5.6.]
*2. OXIDES OF SULFUR
*3. OXIDES OF NITROGEN
The US Environmental Protection Agency and the Acid Deposition Monitoring Network in East Asia: (EANET)
http://www.eanet.asia/
Interrelationships of Global Environmental Issues: ACID DEPOSITION
Interrelationships of Global Environmental Issues," White Paper on the Environment, 2001.
Ministry of the Environment of Japan (2001).