ACID RAIN
BY DYLON GOOKIN AND
TODD RAMSEY
ACID RAIN DEFINITION
• Precipitation, as rain, snow, or sleet,
containing relatively high concentrations of
acid-forming chemicals, as the pollutants
from coal smoke, chemical manufacturing,
and smelting, that have been released into
the atmosphere and combined with water
vapor: harmful to the environment.
SERIES OF EQUATIONS
• S (in coal) + O2  SO2 • These equations show
the step-by-step process
• 2 SO2 + O2  2 SO3
from the burning of coal
to the forming of acid
• SO3 +H20  H2SO4
rain, or sulfuric acid in
aqueous form.
• 2 NO2 + H2O 
HNO2 + HNO3
• This Reaction shows
how Nitrogen dioxide
reacts with water to give a
mixture of nitrous acid
and nitric acid.
VEHICLE NITROGEN OXIDE
EMISSIONS
• At the high temperatures found in the gasoline and
diesel engines of cars and trucks, N2 and O2 react to
form a small quantity of NO which can be oxidized in the
air to form NO2. The NO2 absorbs energy from the
sunlight, and then decomposes into Nitric Oxide and
Oxygen atoms. These atoms react with O2 to form O3.
The ozone then decomposes into O2 and O. The O then
reacts with water to form hydroxyl radicals. These
hydroxyl radicals (OH) react with NO2 (emission) to form
HNO3.
INDUSTRY SULFUR OUTPUT
• Coal burnt in industrial plants for energy
often contains sulfur. Due to petroleum
shortage, coal is being used more and
more often and with higher sulfur
concentrations. The sulfur in the coal
reacts with O2 to form SO2 which further
reacts with Oxygen gas again, to form
SO3. The sulfur trioxide, being highly
reactive, reacts with water to form Sulfuric
acid.
EFFECTS OF ACID RAIN
• Acid rain reacts with
– man-made substances such as
• Marble / Limestone Structures
– CaCO3 + H2SO4  Ca + SO4 + H2O + CO2
– Organic Structures
• Forested ecosystems
• Natural Wildlife (Aqueous)
PREVENTION
• Lower sulfur dioxide emissions from power
plants:
– Use a scrubber to blow powdered limestone
(CaCO3) into the combustion chamber, where
it is decomposed to lime and carbon dioxide.
– CaCO3  CaO + CO2
– The lime then combines with the sulfur
dioxide to form calcium sulfite:
– CaO + SO2  CaSO3