This document is a presentation on acid rain submitted by Surendra Kumar Kacchhi to Dr. Garima Pravin panday and Dr. Deepak rajak. It defines acid rain as precipitation with a pH below 5.6 due to dissolved sulfur dioxide and nitrogen oxides from sources like coal burning. The presentation discusses how acid rain forms through chemical reactions in the atmosphere and its harmful effects on trees, aquatic life, buildings, vegetation, and human health. It concludes that the only way to prevent acid rain is by reducing emissions of nitrogen and sulfur oxides from industries.

1. WELCOME

2. RANI DURGAVATI VISHVAVIDYALAY
JABALPUR M.P.
A home Assignment presentation Based on environment chemistry
Session - 2020-21
Topic- Acid rain
SUBMITTED TO :
Dr. Garima Pravin panday
Dr. Deepak rajak
Dept. Of. P.G. Studies &
Research in chemistry and
Pharmacy
SUBMITTED BY :
SURENDRA KUMAR KACHHI
M.Sc. 2nd semester
Dept.of P.G.Studies &Research
in Chemistry and Pharmacy

3. CONTENTS :
 INDRODUCTIOND
WHAT IS ACID RAIN ?
DEFINITION
HOW DO WE MEASURE THE LEVEL OF ACID IN THE
PRECIPITATION?
CAUSES OF ACID RAIN
CHEMICAL EQUATIONS
FORMATION OF ACID RAIN
EFFECTS OF ACID RAIN ON TRESS , AQUATIC LIFE, BUILDINGS ,
VEGETATION AND HUMAN HEALTH
PREVENTION OF ACID RAIN

4. According to the Royal Society of Chemistry, which
considers him the “father of acid rain,” the word acid
rain was invented in 1852 by Scottish chemist Robert
Angus Smith. Smith decided on the word while
studying rainwater chemistry near industrial towns in
England and Scotland.
INTRODUCTION

5. WHAT IS ACID RAIN ?
Acid Rain is the Precipitation that has a pH of
less than that of natural rainwater (which is
about 5.6due to dissolved carbon dioxide).
It is formed when sulphur dioxides and
nitrogenoxides, as gases or fine particles in the
atmosphere,combine with water vapour and
precipitate as sulphuric acid or nitric acid in
rain, snow, or fog.

6. DEFINITION
• Precipitation, as rain, snow, orsleet, containing
relatively high concentrations of acid-forming
chemicals, as the pollutants from coal smoke,
chemical manufacturing, and smelting,that have
been released into theatmosphere and combined
with water vapour harmful to the environment.
• Acid rain" is a broad term referring to a mixture of
wet and dry deposition (deposited material) from
the atmosphere containing higher than normal
amounts of nitric and sulphuric acids.

7. HOW DO WE MEASURE THE LEVEL OF ACID IN THE
PRECIPITATION?
 The scaleruns from 0 to 14 with
water having a neutralpH of 7.
 pH greater than 7 tells us that
it's an alkaline substance while a
pH less than 7 indicates an acidic
substance.
One unit of pH change equals a
10 time change in the of
concentration of hydrogen ions.
Normal rainand snow measure
about pH 5.60.

8. CAUSES OF ACID RAIN
NATURAL SOURCES : Emissions from volcanoes and from
biological processes that occur on the land, in wetlands,
and in the oceans contribute acid-producing gases to the
atmosphere Effects of acidic deposits have been detected
in glacial ice thousands of years old in remote parts of the
globe.
HUMAN SOURCES: The principal cause of acid rain is
from human sources Industrial factories, power-
generating plantsand vehicles Sulphur dioxide and oxides
of nitrogen are released during the fuel burning process.

9. CHEMICAL EQUATIONS
Both sulphuric acid and nitric acid are soluble in water and
are the major acids present in acid rain. As this forms and
falls onto the Earths surface, these strong acids are
alsobrought to the surface causing harmful effects on the
built and the natural environment.
.Sulfur dioxide reacts with water to form sulfurous acid.
 SO2(g) + H2O(l) →H2SO3(aq)
 Substances in the upper atmosphere then catalyze the
reaction between sulfurous acidand oxygen to form
sulfuric acid.
 2H2SO3(aq) + O2(g) →2H2SO4(aq)

10. CHEMICAL EQUATIONS
Similarly, nitrogen dioxide reacts with water to form
a mixture of nitric acid and nitrous acid.
2NO2(g) + H2O(l)→HNO3(aq) + HNO2(aq)
Substances in the atmosphere then catalyze the
reaction between nitrous acid and oxygen causing
the formation of more nitric acid.
2HNO2(aq) + O2(g) →2HNO3(aq)

11. FORMATION OF ACID RAIN
When water vapour
condenses, or as the rain
falls, they dissolve in the
water to form sulphuric
acid (H2SO4) and nitric
acid (HNO3).
While the air in cleaned
of the pollutants in this
way, it also causes
precipitation to become
acidic, forming acid rain.

12. Sulphur dioxide and nitrogen dioxide undergo
oxidation, and then they react with water resulting in
the formation of sulphuric acid and nitric acid
respectively. The following reaction will clarify the
acid formation reaction:
2SO2 (g) + O2 (g) + 2H2O (l) → 2H2SO4 (aq)
4NO2 (g) + O2 (g) + 2H2O(l) → 4HNO3 (aq)
Formation of acid rain

13. EFFECTS OF ACID RAIN
• Trees : The needles and leaves
of the trees turnbrown and fall
off.
• Trees can also suffer
fromstunted growth; and have
damaged bark andleaves, which
makes them vulnerable
toweather, disease, and insects.
• The soil poisons the tree with
toxic substances that the rain
has deposited into it.
• Acid rain is an extremely destructive form of pollution, and
the environment suffers from its effects Forests, trees,
lakes, animals, and plantssuffer from acid rain.

14. EFFECTS ON AQUATIC LIFE
Lakes are also damaged by acid
rain.Fish die off, and that removes
the main source of food for birds.
Acid rain can even kill fish before
they are born when the eggs are
laidand come into contact with the
acid.
Fish usually die only when the acid
level of alake is high; when the acid
level is lower,they can become sick,
suffer stunted growth,or lose their
ability to reproduce.Also, birds can
die from eating "toxic" fishand
insects.

15. EFFECTS ON BUILDINGS
• Acid rain dissolves the
stonework and mortar of
buildings(especially those
made out ofsandstone or
limestone).
• It reactswith the minerals in
the stone toform a powdery
substance thatcan be
washed away by rain.
• Accelerates weathering in
metaland stones structures .
• Eg.Taj Mahal in Agra , India .
CaCO3 + H2SO4 →
CaSO4 + H2O+ CO2

16.  Statue of Liberty : which is made of
copper has also been damaged by the
cumulative action of acid rain & oxidation for
over 30 years and is, therefore, becoming
green.

17. HARMFUL TO VEGETATION
Increased acidity in soil
.Leeches nutrients from
soil, slowing plant growth .
Leeches toxins from soil,
poisoning plants .
Creates brown spots in
leaves of trees, impeding
photosynthesis .
Allows organisms to infect
through broken leaves.
Eg. Effect on citrus fruits.

18. AFFECTS HUMAN HEALTH
Respiratory problems, asthma, dry coughs,headaches and
throat irritations.
Leeching of toxins from the soil by acid rain canbe absorbed
by plants and animals.
When consumed, these toxins affect humans severely.
Brain damage, kidney problems, and Alzheimers disease has
been linked to people eating "toxic"animals/plants.
Research carried out inNorth America in 1982,revealed that
sulphur pollution killed 51,000people and about 200,000
people become ill as a result of the pollution.

19. 1. The only precaution that we can take against acid rain
is having a check at the emission of oxides of nitrogen
and sulphur.
2. We have so far seen the details of acid rain and its
harmful effect on animals, plants and the monuments.
3. Being responsible citizens, one should be aware of the
harmful effects they cause and of the industries which
give out nitrogen and sulphur compound wastes
unethically.
Prevention of Acid Rain

20. Thank you