1) Acid rain occurs when the pH of rainwater is below 5.6 due to atmospheric pollution from gases like sulfur and nitrogen released by natural sources like volcanoes and human sources like fossil fuel burning. 2) Acid rain adversely affects humans, animals, plants and infrastructure by causing respiratory issues in humans, nutrient deficiencies in animals and vegetation, forest damage, and corrosion of buildings. 3) To prevent further acid rain, emissions of sulfur and nitrogen compounds need to be decreased through alternative energy sources, industrial pollution treatment, and purified water.

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? ©