hello friends this is my first to upload something on net .this is a chemistry ppt .on topic air pollution... acid rain ppt. thank you...
AIR POLLUTIONACID RAIN Acid rainis arainor any other form ofprecipitationthat is unusuallyacidic, meaning that it possesses elevated levels of hydrogen ions (lowpH). It can have harmful effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions ofsulfur dioxideandnitrogen oxide, which react with thewatermolecules in the atmosphere to produce acids. Governments have made efforts since the 1970s to reduce the release of sulfur dioxide into theatmospherewith positive results. Nitrogen oxides can also be produced naturally bylightningstrikes and sulfur dioxide is produced byvolcaniceruptions. The chemicals in acid rain can cause paint to peel,corrosionof steel structures such as bridges, and erosion of stone statues. What is Acid Rain..? Combustion of fuels produces sulfur dioxide and nitric oxides. They are converted into sulfuric acid and nitric acid. Gas phase chemistry: In thegas phasesulfur dioxide is oxidized by reaction with thehydroxylradical via an intermolecular reaction: SO2 (g)+ OH HOSO2 Which is followed by: HOSO2 + O2 (g) HO2 (l) + SO3 In the presence of water,sulfur trioxide (SO3) is converted rapidly tosulfuric acid: SO3(g) + H2O (l) H2SO4(aq) Nitrogen dioxidereacts with OH to form nitric acid: NO2+ OH HNO3 Chemical processes: Chemistry in cloud droplets: When clouds are present, the loss rate of SO2is faster than can be explained by gas phase chemistry alone. This is due to reactions in the liquid water droplets. Sulfur dioxide dissolves in water and then, like carbon dioxide,hydrolysesin a series ofequilibriumreactions: SO2(g) + H2O SO2H2O SO2H2OH++ HSO3 HSO3H++ SO32There are a large number of aqueous reactions thatoxidizesulfur from S(IV) to S(VI), leading to the formation of sulfuric acid. The most important oxidation reactions are withozone,hydrogen peroxideandoxygen(reactions with oxygen are catalyzed byiron andmanganesein the cloud droplets).
Burning coal. Oil and natural gas in power stations makes electricity, giving off sulphur dioxide gas.
Burning petrol and oil in vehicle engines gives off nitrogen oxides as gases.
These gases mix with water vapour and rainwater in the atmosphere producing weak solutions of sulphuric and nitric acids which fall as acid rain.
Causes of Acid Rain
The Problem ! People probably couldn't live without electricity! Therefore coal will continue to be burnt. Also, electricity and energy are constantly being overused.
Think of it this way: every time you turn on a light switch or the television set without really needing to, you're indirectly contributing to the acid rain problem.
Acid rain can travel long distances.
Often it doesnt fall where the gas is produced. High chimneys disperse (spread) the gases and winds blow them great distances before they dissolve and fall to Earth as rain. Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate changes to low pH and are killed.
Acid rain is an extremely destructive form of pollution, and the environment suffers from its effects. Forests, trees, lakes, animals, and plants suffer from acid rain. TreesThe needles and leaves of the trees turn brown and fall off. Trees can also suffer from stunted growth; and have damaged bark and leaves, which makes them vulnerable to weather, disease, and insects. All of this happens partly because of direct contact between trees and acid rain, but it also happens when trees absorb soil that has come into contact with acid rain. The soil poisons the tree with toxic substances that the rain has deposited into it.
How Acid Rain Affects The EnvironmentLakes: 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 laid and come into contact with the acid.
Fish usually die only when the acid level of a lake 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" fish and insects.
Acid rain dissolves the stonework and mortar of buildings (especially those made out of sandstone or limestone).It reacts with the minerals in the stone to form a powdery substance that can be washed away by rain.
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Currently, both the railway industry and the aeroplane industry are having to spend a lot of money to repair the corrosive damage done by acid rain. Also, bridges have collapsed in the past due to acid rain corrosion.
Humans can become seriously ill, and can even die from the effects of acid rain. One of the major problems that acid rain can cause in a human being is respiratory problems. Many can find it difficult to breathe, especially people who have asthma. Asthma, along with dry coughs, headaches, and throat irritations can be caused by the sulphur dioxides and nitrogen oxides from acid rain.
Acid rain can be absorbed by both plants (through soil and/or direct contact) and animals (from things they eat and/or direct contact). When humans eat these plants or animals, the toxins inside of their meals can affect them. Brain damage, kidney problems, and Alzheimer's disease has been linked to people eating "toxic" animals/plants
Research carried out in North America in 1982, revealed that sulphur pollution killed 51,000 people and about 200,000 people become ill as a result of the pollution
What are the solutions to acid rain?
Ride your bike
Tell your friends and family about pollution
Make sure your parents get pollution checks on their cars
Ride the school bus
Learn more; stay up to date
Join a group to stop pollution
Encourage your parents to carpool to work
Switch off lights, fan, heat, etc. when you leave the room
We only have one world.....Do you want it like this?
Made By: Ashish Ranjan xi th -B