Acid Rain ppt for BS course

2. Prepared By:
 Zainab amjad
 Natasha
 Uzma
 Fakhra
 sadaf

3. Acid Rain!
 Acid rain is a rain or any other form of precipitation
which is usually acidic i.e. elevated level of hydrogen
ions (low PH).
 “Acid rain” is a popular term refer to “acid
deposition”.
 PH lower than 4.6 to 5.6
 Contains unnatural acid.
 Term was first considered to be important about
20 years ago when scientists in Sweden and
Norway first believed that acidic rain may be

4. Types of acid deposition!
 Two types:
 Wet deposition
 Dry deposition

5.  Wet deposition:
 Wet deposition of
acids occurs when any
form of precipitation
(rain, snow,fog etc.)
removes acids from
the atmosphere and
delivers it to the
Earth's surface.
 Dry deposition:
 Dry deposition occurs
when particles and
gases stick to the
ground, plants or
other surfaces.
 This can be
responsible for as
much as 20 to 60% of
total acid deposition.

6. Causes of Acid Rain:
 Two main pollutants, causes acid rain:
 SO2
 NO2
 These pollutants add to our environment
bcz of two types of phenomenon.
 Anthropogenic activities.
 Natural phenomenon.

7.  Natural phenomenon:
 Volcanoes
 Forest fire
 Biological processes
 lightning
 Anthropogenic activities:
 Industries
 Vehicles
 Nuclear plants
 Power generation plants
 Brick kilns

10. Chemical Reactions:
 SO2 + H2O  H2SO4
 2NO2 + H2O  2HNO3

11. Effects of Acid Rain:
 Effects on Human being.
 Effects on plants.
 Effects on buildings and sculptures.
 Effects on soil quality.
 Effects on water quality.
 Effects on animals and birds.

12. Acid rain damages man
made structures and
material.
 Dissolve limestone, sand
stone, marble, ceramics and
metals etc.
 So badly damage the
buildings, monuments and
sculptures.
 As they lose their features
when exposed to acid rain.
 Also destroy the textile,
paints, rubber and leather.

14. Acid rain destroys the forests:
 It corrodes the waxy protective coating of the leaves.
 It results in making the plant susceptible to disease.
 The plant loses its ability to produce sufficient amounts of
nutrition for it to stay healthy.
 Once weakened, the plant becomes vulnerable to the cold
weather, insects, and disease, which can lead to its death.
 Dissolving toxic substances in the soil, such as aluminum,
which get absorbed by the roots.
 Also dissolves the beneficial minerals and nutrients in the
soil, which are then washed away before the plants and
trees have a chance of using them in order to grow.

16. Effects of acid rain on humans:
Acid rain harm us via the atmosphere as
well as the soil where the food we eat is
grown.
Contaminated food can damage the nerves
in children, or result in severe brain
damage, or even death.
Causes the toxic metals to be released they
can infiltrate into the drinking water, and the
animals or crops that human use as source
of food.
Aluminum, one of the toxic metals affected
by acid rain, is associated with Alzheimer’s
disease.
The emissions of nitrogen oxide and sulfur
dioxide cause respiratory problems like
throat, nose and eye irritation; headache;
asthma;
Acid rain is particularly harmful for those
who have difficulty in breathing or suffer
from asthma. In fact, even the lungs of
healthy people can be damaged by the
pollutants in acid air.

17. Effects of acid rain on aquatic life:
 A high amount of sulfuric acid interferes with the ability of fish to
take in nutrients, salt, and oxygen.
 As far as freshwater fish is concerned, the molecules of acid
result in mucus forming in their gills, which prevents them from
absorbing oxygen in adequate amounts.
 The acidity, which reduces the pH level, causes the imbalance
of salt in the tissues of fish.
 Change in the pH level also impairs the some of the fish’s
ability to maintain their calcium levels.
 The eggs become to weak or brittle.
 Lack of calcium also causes deformed bones and weakened
spines.

19. Effects on animals & birds:
Animals and birds, like waterfowl or
beavers, which depended on the water for
food sources or as a habitat, begin to die
due to Acid Rain.
Due to the effects of acid rain, animals
which depended on plants for their food
also begin to suffer.
Tree dwelling birds and animals also begin
to languish due to loss of habitat.

21. Strategies to prevent motherStrategies to prevent mother
earth:earth:
• Lakes that have become highly acidic, can be
treated by adding large quantities of alkaline
substances like quicklime, in a process called
liming.
• Limit the quantity of emissions released in the
atmosphere.
• Industries which use coal as fuel have begun to
wash the coal before using it.
• Several industries have added scrubbers to their
smoke stacks to reduce the amount of SO2

22. ……continued
• A reduction in use of vehicles will reduce the
amount of emission caused by our vehicles.
• Reduce use of electric power. Switch off lights,
and other electrical appliances when not
required.
• Increasing awareness is one way of ensuring
that things are done to solve this global problem.
• Join some group which works to protect the
environment. When people get together and
speak with one voice they are more likely to be