High above our heads, in the stratosphere, at an altitude of 19-48 km, the planet is surrounded by ozone. This is a type of oxygen. If an oxygen molecule in air consists of two oxygen atoms joined together - O2, then a molecule that has three atoms is designated by the ozone formula - O3. It is created by sunlight. When ultraviolet rays from the sun pass through the atmosphere, they destroy the usual diatomic oxygen molecules. Each released atom joins the neighboring O2. So the chemical formula of ozone is formed - O3.
What is ozone?
This gas was first discovered by the French physicists Fabry and Buisson. They in 1913 determined that the sun's rays with a wavelength of 200 to 300 nm are actively absorbed by the Earth’s atmosphere. The term "ozone" in Greek means "fragrant", "fragrant." Everyone knows the characteristic smell of this gas that occurs after a thunderstorm. Oxygen is present in the atmosphere in three allotropic forms: O2 - molecular, O - atomic, and O3 - the ozone formula, which is obtained by the chemical combination of the first two.
Gas properties
The ozone layer is quite thin, almost imperceptible. If all the molecules of this gas, which occupy 29 km of space, were combined into a single solid ball, its thickness would occupy only a third of a centimeter. Some ozone is in the air above the Earth’s surface. When automobile exhaust or smog is released into the air, sunlight, reacting with the chemical elements of the emissions, forms ozone. It is especially felt on a hot day, in the air filled with smog, because it reaches a level that threatens health. The formula of the ozone substance is physically unstable, and when its concentration in air is more than 9%, the gas explodes, therefore its storage is possible only at low temperatures. When cooled to -111.9 0 C, the gas turns into a liquid.
Excess ozone
A person cannot live in pure oxygen, a small amount of ozone in the atmosphere is useful to him, but an excessive concentration of it can be deadly. You do not need to inhale it, because this form of oxygen can damage the lungs. Athletes who breathe in a large amount of air saturated with ozone may complain of heaviness and pain when inhaling. Trees and plants growing along the highway, where the air is saturated with exhaust gases, also suffer from excess ozone. This characteristic of this gas is above the surface of the earth. Its natural content (one part of it for tens of millions of other parts of the air) takes part in oxidative processes that occur at the cellular level in the human body. In the ozone formula, only one oxygen atom acts as an oxidizing agent, and the two remaining ones are released as free oxygen.
Beneficial features
When using fully purified indoor air, the researchers noticed an increase in the number of diseases of people in them. The reason was simple - the lack of ozone in the purified air led to disorders in the body. Regular small doses of gas are also useful for disease prevention.
What is the effect of gas? Given the results of the experiments, scientists came to the conclusion that ozone leads to the destruction of almost all naturally occurring viruses, bacteria, protozoa, as well as mold and yeast. In a few minutes, a small portion (ozone formula O3) in a liter of air neutralizes all substances hazardous to humans. After all, ozonation is a natural process common to the body. Even in the room, ozone freshens the air, virtually eliminates the risk of contracting diseases that are transmitted by airborne droplets, neutralizes smoke, dust and allergens, compounds of heavy metals and other harmful air components. Decomposing into water, oxygen and carbon dioxide, these compounds lose their toxicity, unpleasant odors are removed. Given the formula of ozone in chemistry, its high oxidation ability is increasingly being used to disinfect air and water for drinking.
A layer 20 kilometers above the Earth’s surface actually protects our health by absorbing ultraviolet rays. It acts as a filter, protecting the Earth from harmful ultraviolet radiation. Without a protective layer, life on the planet would not have been possible. It is proved that the flora and fauna appeared on Earth only when a powerful shield was formed, protecting it from solar radiation. Ultraviolet helps the skin acquire a beautiful tan, but at the same time, it is the main culprit for sunburn and skin cancer.
The ozone hole
In the 70s, scientists studying the ozone layer above the planet found that chemicals used in refrigerators, air conditioners, and aerosols can destroy ozone. Gases enter the air every time these devices are repaired or when various aerosols are sprayed. According to scientists, harmful gases, in the end, reach the ozone molecules. In this case, solar radiation releases chlorine from chlorofluoride hydrocarbons, which destroys the structural formula of ozone, turning it into ordinary oxygen. Thus, the protective layer is destroyed. After another 15 years, British scientists made an amazing discovery: a huge hole in the ozone layer was located above Antarctica. This hole appears every spring and reaches approximately the size of the United States. When the direction of the wind changes due to changing seasons, the hole is again filled with ozone molecules. In this case, a certain number of molecules fills the hole, and in other parts the gas layer becomes thinner.
What threatens to reduce the protective layer?
In the winter of 1992, the ozone layer over Europe and Canada became thinner by 20%. In areas where this layer is not dense enough and is not able to filter out strong radiation, the incidence of skin cancer is very noticeable. Above Antarctica, scientists recorded an extremely high level of chlorine monoxide, which is formed as a result of the destruction of ozone by chlorine. Researchers estimate that the loss of only 1% of the protective layer leads to an increase in the amount of ultraviolet radiation on Earth by 2%, and with it, the number of skin cancer diseases increases by 3-6%. Ultraviolet radiation also destroys the body's immunity, making a person more defenseless against infections. Ultraviolet can damage the cells of all plants, from cereals to trees.
Since the ozone layer retains heat, when it decreases, the air at this latitude cools, changing the winds and weather in the world. It is difficult to predict what impact the layer depletion will have on the climate in the future, scientists predict the drying of natural zones, the loss of some vegetation and the insufficient amount of food if the problem of the destruction of this gas is not solved. Even with the cessation of human activity, which entails emissions of gases that destroy the protective layer, it would take him at least 100 years to return to the previous level.