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The impact of ozone on human health is controversial. For many years now, there has been an in-depth study of the effects of ozone, because the concept of ozone is air is not entirely correct. Find out more about it, and then you can say with confidence whether ozone is your friend or not.

Ozone is practically oxygen; it doesn’t even have a separate cell in the periodic table. By chance, the oxygen atoms connected in threes, and not in twos, as usual. At one time, a Dutch physicist, conducting experiments, discovered this discrepancy. In order to understand what it is ozone, and what about oxygen, it’s worth saying in more detail. Oxygen is the air we breathe every minute, but ozone is the smell of the air after a thunderstorm. A thunderstorm acts in this way, by the power of its magnetism, it forces oxygen to combine in three atoms, and as a result, what happens is what happens. Rarely, but still such a connection occurs under the influence of certain chemical compounds. And although ozone is considered and is an integral component of air, the official date of its appearance is considered to be 1840, which means that ozone is a fairly young component of air. Translated, ozone means smelling, the fact that it smells is a proven fact, but it’s difficult to talk about everything else, since scientists have not come to a consensus, and unfortunately no one can say what is more harmful or beneficial in it.

For information, in the United States of America, the ozone therapy method is quite in demand, and as statistics show, such treatment copes with a huge number of diseases; at the moment, the practice of ozone treatment is also included in Russia. But here infectious disease specialists intervene, they say that using this method in human body can hit very a large number of viruses, which as a result can mutate and this is already serious. But they cannot back up their words with facts. Then it is too early to assume and talk about it. The following should be noted from ozone treatment, the first is blood vessels. Blood enriched with ozone improves microcirculation in the capillaries of the skin, thereby reducing swelling and inflammation, both external and internal. Ozone also has a divine positive effect on all nervous system a person, it is no coincidence that after a noisy metropolis, for example, when you find yourself in a forest, you feel incredibly good both physically and mentally.

Probably, the time is not far off when scientists will finally tell us whether ozone is beneficial or harmful, but the former will most likely be proven, since there can be no harm from ozone, in any case, many, many, both scientists and ordinary residents, are convinced of this planets that want to breathe clean and healthy air.

Atoms of the same type can be part of different substances. For the element designated by the symbol “O” (from the Latin name Oxygenium), there are two known common types in nature: simple substances A. The formula of one of them is O 2, the second is O 3. These are oxygen (allotropes). There are other compounds that are less stable (O 4 and O 8). A comparison of molecules and

modifications?

Many chemical elements can exist in two, three or more forms. Each of these modifications is formed by atoms of the same type. The scientist J. Berzelius was the first to call this phenomenon allotropy in 1841. The open pattern was initially used only to characterize substances with a molecular structure. For example, two allotropic modifications of oxygen are known, the atoms of which form molecules. Later, researchers found that modifications could occur among the crystals. By modern ideas, allotropy is one of the cases of polymorphism. Differences between forms are caused by the mechanisms of formation chemical bond in molecules and crystals. This feature is manifested mainly by elements of groups 13-16 periodic table.

How do different combinations of atoms affect the properties of a substance?

Allotropic modifications oxygen and ozone are formed by atoms of an element with atomic number 8 and the same number of electrons. But they differ in structure, which led to a significant discrepancy in properties.

Conclusions from the comparison: allotropic modifications of oxygen do not differ in qualitative composition. The structure of a molecule affects the physical and chemical properties of substances.

Are the amounts of oxygen and ozone equal in nature?

A substance whose formula is O 2 is found in the atmosphere, hydrosphere, earth's crust and living organisms. About 20% of the atmosphere is made up of diatomic oxygen molecules. In the stratosphere, at an altitude of approximately 12-50 km from the earth's surface, there is a layer called the “ozone screen”. Its composition is reflected by the formula O 3. Ozone protects our planet by intensively absorbing the dangerous rays of the red and ultraviolet spectrum of the Sun. The concentration of the substance is constantly changing, and its low is 0.001%. Thus, O 2 and O 3 are allotropic modifications of oxygen, which have significant differences in distribution in nature.

How

Molecular oxygen is the most important simple substance on Earth. Formed in the green parts of plants in the light. During electrical discharges of natural or artificial origin, the diatomic oxygen molecule disintegrates. The temperature at which the process begins is about 2000 °C. Some of the resulting radicals combine again, forming oxygen. Some active species react with diatomic oxygen molecules. This reaction produces ozone, which also reacts with oxygen free radicals. In this case, diatomic molecules appear. The reversibility of the reactions leads to the fact that the concentration of atmospheric ozone is constantly changing. In the stratosphere, the formation of a layer consisting of O 3 molecules is associated with ultraviolet radiation Sun. Without it protective screen dangerous rays could reach the surface of the Earth and destroy all forms of life.

Allotropic modifications of oxygen and sulfur

The chemical elements O (Oxygenium) and S (Sulfur) are located in the same group of the periodic table; they are characterized by the formation of allotropic forms. From molecules with different amounts sulfur atoms (2, 4, 6, 8) under normal conditions, the most stable is S8, resembling a crown in shape. Orthorhombic and monoclinic sulfur are built from such 8-atomic molecules.

At a temperature of 119 °C monoclinic form yellow color forms a brown viscous mass - a plastic modification. The study of allotropic modifications of sulfur and oxygen has great importance in theoretical chemistry and practical activities.

IN industrial scale are used oxidizing properties different forms. Ozone is used to disinfect air and water. But at concentrations above 0.16 mg/m3, this gas is dangerous for humans and animals. Molecular oxygen is necessary for respiration and is used in industry and medicine. An important role in economic activity allotropes of carbon (diamond, graphite, red) and other chemical elements play.

characterize and compare allotropic modifications of oxygen, physical and Chemical properties, methods of producing oxygen and ozone, their practical significance; the importance of the ozone layer for life on Earth;

explain the essence of allotropy;

draw up equations and electronic balance diagrams for the corresponding chemical reactions.

Oxygen and ozone. Oxygen forms two simple substances: oxygen O2 and ozone O3. Mr (O2) = 32, Mr (O3) = 48.

In nature, ozone is formed in the atmosphere from oxygen during lightning electrical discharges. The characteristic smell of freshness that we smell after a thunderstorm is the smell of ozone. Phenomenon of existence chemical element in the form of two or more simple substances, different in properties and structure, is called allotropy, and the simplest substances are allotropic modifications (forms, modifications) of a chemical element.

Oxygen O2 and ozone O3 are allotropic modifications of the chemical element oxygen.

What is the reason for the different properties of allotropic modifications, namely oxygen and ozone? You already know that the properties of a substance are determined by its composition and structure.

Oxygen and ozone have the same high-quality composition, but different quantitative; identical molecular structure, but different spatial structure of the molecules: linear - in the non-polar oxygen molecule and angular - in the polar ozone molecule. So, in addition to being similar, these substances have different properties.

— Make electronic balance diagrams for each equation. Explain how the presence of manganese (IV) oxide floats away during the decomposition reactions of H2O2 and KClO3.

In the laboratory, ozone is produced in special devices— ozonizers made of oxygen under the influence of an electric discharge (Fig. 36).

Chemical properties of allotropic modifications of oxygen. The high electronegativity of oxygen results in strong oxidizing properties of its allotropic modifications.

You know that oxygen is highly reactive. It reacts with most simple substances to form oxides.

The use of oxygen on an industrial scale began in the mid-20th century. — After the invention of a device for liquefying and separating air. As an oxidizing agent, it is used in metallurgy to produce steel using the converter method, cutting metals, in a mixture with other oxygen-rich compounds - for the oxidation of rocket fuel, in gas mixtures for breathing during underwater work, in medicine for respiratory failure.

The use of ozone is due to its very high reactivity. It is used for disinfection drinking water, cleaning flue gases, industrial and household Wastewater, bleaching fabrics, and also as an oxidizer for rocket fuel.

Physiological action of O3. It should be remembered that the extreme oxidizing power of ozone results in its toxic effects on humans, animals and plants. Even small concentrations of ozone that exceed natural levels cause irritation of the respiratory tract, coughing, vomiting, dizziness, and fatigue. Such symptoms can be observed in major cities, where increased vehicle emissions containing nitrogen oxides cause the conversion of oxygen to ozone.

Ozone reaches its maximum concentration in the atmosphere at a distance of 23–25 km from the Earth’s surface, forming the so-called ozone layer.

The ozone layer plays an important role in preserving life on our planet. It blocks harmful ultraviolet solar radiation that is harmful to people, animals and plants, which can cause skin diseases (including cancer) and negatively affect biological processes. In addition, along with carbon dioxide The ozone layer absorbs heat, infrared radiation The earth and prevents it from cooling.

However, under the influence of anthropogenic factors, the ozone layer undergoes destruction, and “ozone holes” form in it. There are dozens of known air pollutants that destroy the ozone layer. Scientists have studied that nitrogen oxides, which are formed during the operation of aircraft engines, are especially dangerous. According to the degree of influence of other substances, it is in natural conditions not completely determined.

Preservation and restoration of the ozone layer, establishing the causes of its destruction is one of the most pressing problems of humanity, which requires a solution.

Briefly about the main thing

Oxygen forms two allotropic modifications - oxygen O2 and ozone O3, which differ in the composition and structure of the molecule and, accordingly, properties. The existence of a chemical element in the form of two or more simple substances, different in properties and structure, is called allotropy, and the simplest substances are allotropic modifications (forms) of the chemical element. Allotropic modifications of oxygen - oxygen O2 and ozone O3 - are strong oxidizing agents, which manifests themselves in reactions with most simple substances and many complex ones. The products of oxidation reactions with oxygen are usually oxides. The oxidizing capacity of ozone O3 is higher than that of oxygen O2, which is due to the formation of exclusively active oxygen atoms.