What is Acid Rain, Effects, Mitigation Measures

1. ACID
RAIN
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2. History
The term was coined in
1872 by the Scottish
chemist Robert Angus
Smith to describe the
acidic precipitation in
Manchester, England.
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3. When is Acid Rain
ACID Rain?
When the pH of rain water is
<5.6, it is called Acid Rain.
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4. When is Acid Rain
ACID Rain?
Acid Rain
pH < 5.6
Normal Rain
pH = 7
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5. Adverse Effects at
what pH?
• Adverse Effects of Acid Rain
start only below pH 4.5
• North America, Central
Europe, Netherlands,
Sweden, USA and other
countries having acid rain
between 2.0 and 5.0.
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6. Acid Rain in INDIA
Delhi, Uttar Pradesh,
Maharashtra, Madhya
Pradesh, Tamil Nadu and
even the Andaman Islands
have reported low levels of
pH.
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7. ACID RAIN
formulas
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8. Acid Rain Formulas
• CO2 + H2O =
• 2NO + O2 =
• 4NO2 + H20 + O2 =
• 2SO2 + O2 =
• SO3 + H2O =
• HCl gas Dissolved in
Water
H2CO3
2NO2
4HNO3
2SO3
H2SO4
HCl acid
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9. Acid Rain Formulas
H2SO4 - 70% contribution to
Acid Rain
• 4HNO3 - 20% contribution to
Acid Rain
• 10% others ©

10. CAUSES
of
ACID RAIN
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11. CAUSES of Acid Rain
• Mainly Air Pollution – by gases
like SOX and NOX released by
Natural Causes
&
Man-Made causes
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12. CAUSES of Acid Rain
NATURAL
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13. CAUSES of Acid Rain
1. Release of Gases through
Volcanic Eruptions.
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14. CAUSES of Acid Rain
2. Release of Gases through
Ocean Sprays – Sea Salt Sprays.
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15. CAUSES of Acid Rain
3. Decomposition of Organic
Matter
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16. CAUSES of Acid Rain
4. NOX emitted from Lightening
Thunderstorms
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17. CAUSES of Acid Rain
5. Natural Forest Fires
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18. CAUSES of Acid Rain
6. Soil Organisms
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19. CAUSES of Acid Rain
NATURAL Causes -
1/3rd of the Nitrogen
and Sulphur emissions
in the US.
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20. CAUSES of Acid Rain
MAN-MADE
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21. CAUSES of Acid Rain
1. Release of Gases through
Automobile Exhaust.
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22. CAUSES of Acid Rain
2. Release of Gases through
Burning of Fossil Fuels like – Coal, Oil
and Natural Gas.
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23. CAUSES of Acid Rain
3. Release of Gases through
Manufacturing, oil refineries and
other Industries.
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24. EFFECTS
of
ACID RAIN
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25. EFFECTS of Acid Rain
1. Effects on Humans
• Skin Irritation/Diseases
• Respiratory Problems – Chronic
Bronchitis, Asthma in children, ppl
over 65 years, pregnant women
and ppl with heart diseases.
(by breathing particulates of SOX and NOX.)
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26. EFFECTS of Acid Rain
2. Effects on Animals
• Less Nutrients in animals who
feed on soil as ground nutrients
are leached/destroyed
by Acid Rain.
Calcium
Deficiency in
Snails.
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27. EFFECTS of Acid Rain
3. Effects on Birds
• Death due to deceased
food supply in Acidic
wetlands – North American
Black Duck.
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28. EFFECTS of Acid Rain
3. Effects on Birds
• Perishing of birds due to diet
on insects with less nutrients.
Birds that feed
on Snails.
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29. EFFECTS of Acid Rain
SONGBIRD EGGS
The eggs they lay are defective — thin
and fragile. The chicks either do not
hatch or have bone malformations and
die. ©

30. EFFECTS of Acid Rain
3. Effects on Birds
• Loss of Habitat due to
destruction of Trees.
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31. EFFECTS of Acid Rain
4. Effects on Trees / Vegetation
• Acid Rain decolourises
leaves.
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32. EFFECTS of Acid Rain
5. Effects on Trees / Vegetation
• Reduction of Chlorophyll
content
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33. EFFECTS of Acid Rain
5. Effects on Trees / Vegetation
• Forests exposed to heavy
industrialization are virtually
killed.
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34. EFFECTS of Acid Rain
5. Effects on Trees / Vegetation
• Less Nutrients in the soil to
grow vegetation
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35. EFFECTS of Acid Rain
6. Effects on Water Resources
• Acidification of water
resources - both surface and
underground
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36. EFFECTS of Acid Rain
6. Effects on Water Resources
• Reduction of Aquatic Life.
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37. pH range Effect on Fish
• 6.5–9 No effect
• 6.0–6.4 Unlikely to be harmful except when
carbon dioxide levels are very high (1,000 mg l−1)
• 5.0–5.9 Not especially harmful except when
carbon dioxide levels are high (20 mg I1) or ferric ions
are present
• 4.5–4.9 Harmful to the eggs of salmon and trout
species and to adult fish when levels of Ca2, Na+ and
Cl− are low
• 4.0–4.4 Harmful to adult fish of many types which
have not been progressively acclimated to low pH
• 3.5–3.9 Lethal to salmonids, although acclimated
roach can survive for longer
• 3.0–3.4 Most fish are killed within hours at these
levels
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38. EFFECTS of Acid Rain
7. Effects on Environment
• Makes the weather smoggy.
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39. EFFECTS of Acid Rain
7. Effects on Environment
• Reduction in Soil pH
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40. EFFECTS of Acid Rain
8. Effects on Structure & Property
• Damage to Building Materials
like Plaster, Marble, Limestone
etc.
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41. EFFECTS of Acid Rain
8. Effects on Structure & Property
• Corrosion of Reinforcement by
seepage through cracks.
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42. EFFECTS of Acid Rain
9. Effects on Ecosystem
• Affects the food chain- less
nutrients & less food up the
chain.
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43. PREVENTING
/CURE
of
ACID RAIN ©

44. CURE of Acid Rain
1. Decrease Emissions of SOX
and NOX.
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45. 2. Reduction of use of
Conventional Resources
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CURE of Acid Rain

46. 3. Treatment of Industrial Gases
before emissions
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CURE of Acid Rain

47. CURE of Acid Rain
4. Alternate Energy Resources
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48. CURE of Acid Rain
5. Considering Nuclear Energy
as an option for fuel
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49. CURE of Acid Rain
6. Purification of Polluted Water
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50. Let’s bring an end to
the Acid Rain
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51. ASSIGNMENTS:
Q1 Write the Formulas for
the formation of Acid Rain.
Q2. What are the ill effects
of Acid Rain?
Q3. How to prevent Acid
Rain? ©