|
Dynamics Research
|
Don't worry, be happy!
Ozone or trioxygen (O3) is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic O2. Ground-level ozone is an air pollutant with harmful effects on the respiratory systems of animals. The ozone layer in the upper atmosphere filters potentially damaging ultraviolet light from reaching the Earth's surface. It is present in low concentrations throughout the Earth's atmosphere. It has many industrial and consumer applications.
Ozone, the first allotrope of a chemical element to be recognized by science, was proposed as a distinct chemical compound by Christian Friedrich Schönbein in 1840, who named it after the Greeklightning storms. The formula for ozone, O3, was not determined until 1865 by Jacques-Louis Soret and confirmed by Schönbein in 1867.
Most people can detect about 0.01 ppm in air. Exposure of 0.1 to 1 ppm produces headaches, burning eyes, and irritation to the respiratory passages. At -112 °C, it forms a dark blue liquid. At temperatures below -193 °C, it forms a violet-black solid.
Ozone is diamagnetic, meaning that it will resist formation of a magnetic field and will decrease the energy stored in the field once the field is established.
The structure of ozone, according to experimental evidence from microwave spectroscopy, is bent, with C2v symmetry (similar to the water molecule), O – O distance of 127.2 pm and O – O – O angle of 116.78°. The central atom forms an sp² hybridization with one lone pair. Ozone is a polar molecule with a dipole moment of 0.5337 D. The bonding can be expressed as a resonance hybrid with a single bonddouble bond on the other producing an overall bond order of 1.5 for each side.
Ozone is a powerful oxidizing agent, far better than dioxygen. It is also unstable at high concentrations, decaying to ordinary diatomic oxygen (in about half an hour in atmospheric conditions):
Ozone will oxidize metals (except gold, platinum, and iridium) to oxides of the metals in their highest oxidation state:
Ozone also increases the oxidation number of oxides:
The above reaction is accompanied by chemiluminescence. The NO2 can be further oxidized:
Ozone can be used for combustion reactions and combusting gases; ozone provides higher temperatures than combusting in dioxygen (O2). The following is a reaction for the combustion of carbon subnitride which can also cause lower temperatures:
Ozone can react at cryogenic temperatures. At 77 K (-196 °C), atomic hydrogen reacts with liquid ozone to form a hydrogen superoxide radical, which dimerizes:
Ozone can be used to remove manganese from water, forming a precipitate which can be filtered:
Ozone will also turn cyanides to the one thousand times less toxic cyanates:
Finally, ozone will also completely decompose urea:
The standard way to express total ozone levels (the amount of ozone in a vertical column) in the atmosphere is by using Dobson units. Concentrations at a point are measured in parts per billion (ppb) or in μg/m³.
Ozone layer
The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer between about 10 km and 50 km above the surface (or between about 6 and 31 miles). Here it filters out photons with shorter wavelengths (less than 320 nm) of ultraviolet light, also called UV rays, (270 to 400 nm) from the Sun that would be harmful to most forms of life in large doses. These same wavelengths are also among those responsible for the production of vitamin D, a vitamin also produced by the human body. Ozone in the stratosphere is mostly produced from ultraviolet rays reacting with oxygen:It is destroyed by the reaction with atomic oxygen:
The latter reaction is catalysed by the presence of certain free radicals, of which the most important are hydroxyl (OH), nitric oxide (NO) and atomic chlorine (Cl) and bromine (Br). In recent decades the amount of ozone in the stratosphere has been declining mostly because of emissions of CFCs and similar chlorinated and brominated organic molecules, which have increased the concentration of ozone-depleting catalysts above the natural background. Ozone only makes up 0.00006% of the atmosphere.
Ozone reacts directly with some hydrocarbons such as aldehydes and thus begins their removal from the air, but the products are themselves key components of smog. Ozone photolysis by UV light leads to production of the hydroxyl radical OH and this plays a part in the removal of hydrocarbons from the air, but is also the first step in the creation of components of smog such as peroxyacyl nitrates which can be powerful eye irritants. The atmospheric lifetime of tropospheric ozone is about 22 days; its main removal mechanisms are being deposited to the ground, the above mentioned reaction giving OH, and by reactions with OH and the peroxy radical HO2· (Stevenson et al., 2006).
There is evidence of significant reduction in agricultural yields because of increased ground-level ozone and pollution which interferes with photosynthesis and stunts overall growth of some plant species.
Certain examples of cities with elevated ozone readings are Houston, Texas, and Mexico City, Mexico. Houston has a reading of around 41 ppb, while Mexico City is far more hazardous, with a reading of about 125 ppb.
Although ozone was present at ground level before the Industrial Revolution,
peak concentrations are now far higher than the pre-industrial levels,
and even background concentrations well away from sources of pollution
are substantially higher. This increase in ozone is of further concern
because ozone present in the upper troposphere acts as a greenhouse gas, absorbing some of the infraredclimate change (the IPCC Third Assessment Report) suggests that the radiative forcing of tropospheric ozone is about 25% that of carbon dioxide.
1. First - Ozone produced by plants and trees has small chances to
survive in the crossing and the lifting of the atmosphere to shield the
Earth's ozone. Afforestation should be increased, but this process is
long and insufficient.
2. Second - Ozone produced from ultraviolet rays is not sufficient.
3. Third
- A large quantity of ozone is produced by lightnings during storms.
Since we have a large deficit of high ozone (where it is absolutely
necessary) should produce ozone industrial (in large quantities) to
great heights by artificial lightning, man-made. One has to hurry this
process, especially now when because the nuclear experiments we have a
large deficit of ozone at high heights (and even a hole in the "Ozone
Shield", which must be disposed of emergency). The first artificial
lightning which already can one uses, is the cold plasma.
In the cold plasma method, pure oxygen gas is exposed to a plasma created by dielectric barrier discharge. The diatomic oxygen is split into single atoms, which then recombine in triplets to form ozone.
Cold plasma machine utilizes
pure oxygen as the input source and produce a maximum concentration of
about 5% ozone. It produce far greater quantities of ozone in a given
space of time compared to ultraviolet production. It has the aspect of
a Lightning.
These machines will be located at high altitudes, the high peak mountains.
Lightning is
an example of plasma present at Earth's surface. Typically, lightning
discharges 30,000 amperes, at up to 100 million volts, and emits light,
radio waves, x-rays and even gamma rays.[13] Plasma temperatures in lightning can approach ~28,000 kelvin (~27,700°C) and electron densities may exceed 1024/m³.
At
an average number of about 300 per second that lightning hit the
earth's atmosphere, with a hole of about 10% of world land area, we
needed about 30 lightning machines only this machines have a ritm of
one lightning per second. If this rate can not be sustained or the
power and flow will be lower than those of an average lightning known,
then will put more machines accordingly.
Create a free website at Webs.com