atmospheric components and ozone

8/7/2019 Atmospheric Components and Ozone

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Nitrogen (N2) 78.08%

Oxygen (O2) 20.95%

Argon (Ar) 0.93%

Neon, Helium,

Krypton0.0001%


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Variable Components

Carbon dioxide (CO2) 0.038%

Water vapor (H20) 0-4%

Methane (CH4) trace

Sulfur dioxide (SO2) trace

Ozone (O3) trace

Nitrogen oxides (NO, NO2, N2O) trace


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Composition of dry atmosphere, by volume[2]

Gas Volume

Nitrogen (N2) 780,840 ppmv (78.084%)

Oxygen (O2) 209,460 ppmv (20.946%)

Argon (Ar) 9,340 ppmv (0.9340%)

Carbon dioxide (CO2) 390 ppmv (0.039%)

Neon (Ne) 18.18 ppmv (0.001818%)

Helium (He) 5.24 ppmv (0.000524%)Methane (CH4) 1.79 ppmv (0.000179%)

Krypton (Kr) 1.14 ppmv (0.000114%)

Hydrogen (H2) 0.55 ppmv (0.000055%)

Nitrous oxide (N2O) 0.3 ppmv (0.00003%)

Carbon monoxide (CO) 0.1 ppmv (0.00001%)

Xenon (Xe) 0.09 ppmv (9106

%) (0.000009%)

Ozone (O3) 0.0 to 0.07 ppmv (0 to 7106%)

Nitrogen dioxide (NO2) 0.02 ppmv (2106%) (0.000002%)

Iodine (I2) 0.01 ppmv (1106%) (0.000001%)

Ammonia (NH3) trace

Not included in above dry atmosphere:

Water va or H O~0.40% over full atmosphere, typically 1%-4% at


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Argon


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Rayleigh scattering


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Figure 1: Craters on the far side of the moon (L) and

Manicouagan crater in Quebec (R). Image courtesy of NASA.


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Ozone Molecule


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What the Ozone Layer Does


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Low level ozone

Low level ozone (or tropospheric ozone) is anatmospheric pollutant. It is not emitted directly bycarengines or by industrial operations, but formed by thereaction of sunlight on air containing hydrocarbonsand nitrogen oxides that react to form ozone directlyat the source of the pollution or many kilometers downwind.

Ozone reacts directly with some hydrocarbons such

as aldehydes and thus begins their removal from theair, but the products are themselves key componentsof smog.


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Usefulness of Ozone Disinfect laundry in hospitals, food factories, care homes etc

Disinfect water in place ofchlorine Deodorize air and objects, such as after a fire. This process is extensively

used in fabric restoration

Kill bacteria on food or on contact surfaces

Sanitize swimming pools and spas

Kill insects in stored grain Scrub yeast and mold spores from the air in food processing plants;

Wash fresh fruits and vegetables to kill yeast, mold and bacteria

Manufacture chemical compounds viachemical synthesis

Clean and bleach fabrics (the former use is utilized in fabric restoration;

the latter use is patented);

Assist in processing plastics to allow adhesion of inks;

Age rubber samples to determine the useful life ofabatch of rubber;

Eradicate water borne parasites

DEGRADE PLASTICS


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Propellant/Foam


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Ozone Depletion


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Ozone Hole


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Carbon Dioxide

A candy called Pop Rocks is pressurized with carbon

dioxide gas at about 40 bar

Leavening agents produce carbon dioxide to cause

dough to rise. Baker's yeast produces carbon dioxideby fermentation of sugars.

arbon dioxide is used to produce carbonatedsoft

drinks and soda water

Fire extinguisher


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Toxicity

1% can cause drowsiness with prolonged exposure.

At 2% it is mildly narcoticand causes increased bloodpressure and pulse rate, and causes reduced hearing.

At about 5% it causes stimulation of the respiratorycenter, dizziness, confusion and difficulty in breathingaccompanied by headache and shortness ofbreath.Panicattacks may also occur at this concentration.

At about8%

it causes headache, sweating, dim vision,tremor and loss ofconsciousness after exposure forbetween five and ten minutes.


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atmospheric components and ozone

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