What is acid rain?
Acid rain is precipitation with a pH less than 5.6. It contains dangerous amounts of nitric and sulfuric
acids, which are formed by sulfur and nitrogen oxides that have been released into the atmosphere from burning fossil fuels,
Unpolluted air has a pH above 5.6. Once the air conatins more nitrogen and sulfur oxides, it becomes more polluted
and acidic causing its pH to fall below 5.6
Where do these chemicals come from?
NOx, or nitrogen oxides, are formed from fuel being burnt at high temperatures. It is formed from
a lot of manmade sources such as cars, electric utilities, and any other source that burns fuel.
SOx, or sulfur oxides, are also formed when fuel is burned or when gas is extracted from oil and metals are extracted
from ore. More than 13 million tons per year of SOx is released into the air from electrical or industrial plants who focus
on using things like ore, coal and oil.
Acid rain effects building materials. It precipitates onto these materials and forms crystals, which
then break off pieces of the mateial. This is also known as corrosion. The most vulnerable materials that it can corrode are:
limestone, marble, carbon-steel, zinc, nickel, paint and some plastics. The chemicals in acid rain can also eat away at fabrics
and discolour them, such as flags.
Acid rain also effects architecture. It causes buildings to corrode from leftover acid depositions
on structures from a rain. Limestone and marble turn into gypsum when effected by acid rain. Some of the most famous sculptures
that have been effected by acid rain include: the Taj Mahal, Notre Dame Cathedral, and the Colosseum.
It also causes our roads, highways, and bridges to corrode and become weaker. This is a huge safety
hazard not only for roads and highways, but also for bridges because if a bridge is weak, it will collapse. It costs a lot
of money to keep replacing the roads, highways and bridges, and it comes out of our tax money.
Cars, trains and buses are effected also by acid rain. They are all weathered from the acid rain precipitate
and suffer the effects of corrosion. These items are mainly made out of iron and steel, so they get very rusted from the acid
The chemical equation for rust is: 4Fe + 3O2 --> 2Fe2 O3. Rust is a red or brown oxide found
on iron or steel. It is found when iron or steel and hydrated oxides combine.
You really can't even ballpark a number to say how much acid rain all costs. It does raise taxes a bit in order for upkeep
on all the buildings, roads and etc. The fisheries, forestry, and agriculture industries are a bit hurt though, because the
water and land is becoming more and more polluted. That means the fish are dying in the water, trees don't have sufficient
living conditions and animals are living in pollution. These things are dying so that equals less money for the people who
control these industries.
What is the effect on trees and soil?
Acid rain gradually gets into the water table and seeps into the soil, making the soil and nutrients more
acidic. Because these nutrients are more acidic, plants don't really want them, causing a nutrient loss in the leaves and
stems of plants. There is a reduction in tree growth also, because they aren't getting the sufficient amount of minerals needed
in the soil to grow.
Acid rain also reduces the rate of decomposition on the forest floor. Because of the pollution, soil
organisms respiration rates are reduced so they can't decompose as quickly as they could. This equals more waste on the forest
floor then decomposed matter, which would effect all the plants and animals around because in an ecosystem, everything is
As lakes and water systems become more acidic from acid rain, they can no longer support the same
kind of species or environment they once could. For example, crayfish and clams are usually the first to die out in the lake,
then the fish, then the birds that feed on the fish.
Some lakes are able to neutralize the acidity because they contain a lot of limestone which has a high alkalinity,
but unfortunately the lakes in Eastern Canada don't have a lot of limestone, they contain granite, and Eastern Canada is where
most acid rain is.
What is the effect of acid rain on humans?
The most serious side effect of acid rain on humans is it damages the respiratory system. The acid rain
precipitation gets into the ground water and frees up the toxic metals that are held together with compounds. The acid rain
breaks down these compounds and the toxic metals wash into our water sources. We drink the water and then we get sick. These
sicknesses include asthma, headaches, dry coughs, and eye, throat and nose infections. Acid rain also raises the amount of
mercury in lakes, so the fish get poisoned and we eat them and get very ill. This also has been linked to brain damage and
nerve disorders in children.
One huge problem also is that the water is so acidic it reacts with the copper and lead water pipes, which
contaminates our water. This can result in major kidney and liver damage.