What forms oxygen. Oxygen - characteristic of an element, abundance in nature, physical and chemical properties, production

Omnipresent, omnipotent and invisible is all about him. It also has no taste or smell. One gets the impression that the conversation is about something that does not exist at all. However, this substance is, moreover: without it, humanity would simply suffocate. Therefore, Lavoisier immediately called this gas "life gas".

Oxygen almighty

According to religious people, only God can be omnipresent, omnipotent and at the same time invisible. In fact, all these three epithets can be easily attributed to a chemical element with atomic number 8 - oxygen. If plants in the process of photosynthesis did not convert water and carbon dioxide in organic compounds, and this process was not accompanied by the release of bound oxygen, then, having exhausted quite quickly the reserves of atmospheric oxygen, the entire animal world including humanity would soon suffocate.

Oxygen is omnipresent: not only air, water and earth, but also you and I, our food, drink, clothing, largely consist of it; the overwhelming majority of the substances around us contain oxygen. The power of oxygen is already manifested in the fact that we breathe it, but breathing is a synonym for life. And oxygen can also be considered omnipotent because the powerful element of fire, as a rule, strongly depends on our candidate for being omnipresent and omnipotent.

As for the third epithet - "invisible", then there is probably no need for proof. At normal conditions elemental oxygen is not only colorless and therefore invisible, but also not perceived, not felt by any sense organs. True, the lack, and even more so the lack of oxygen, we would have felt instantly ...

Discovery: XVIII century

The fact that oxygen is invisible, tasteless, odorless, and gaseous under normal conditions delayed its discovery for a long time. Many scientists in the past guessed that there was a substance with properties that we now know are inherent in oxygen.

Opening oxygen (English Oxygen, French Oxygene, German Sauerstoff) marked the beginning of the modern period in the development of chemistry. It has been known since ancient times that air is needed for combustion, but for many centuries the combustion process remained incomprehensible. Only in the 17th century. Mayow and Boyle independently expressed the idea that there is some substance in the air that supports combustion.

Oxygen was discovered almost simultaneously and independently of each other by two outstanding chemists of the second half of XVIII century - the Swede Karl Wilhelm Scheele and the Englishman Joseph Priestley. Scheele received oxygen earlier, but his treatise On Air and Fire, which contained information on oxygen, was published later than Priestley's discovery.

Joseph
Priestley

“On August 1, 1774, I tried to extract air from the mercury scale and found that air could easily be expelled from it by means of a lens. This air was not absorbed by water. Imagine my amazement when I discovered that a candle burned in this air with an unusually bright flame. I tried in vain to find an explanation for this phenomenon. "

And yet, the main figure in the history of the discovery of oxygen is not Scheele or Priestley. They discovered a new gas - that's all. Later, Friedrich Engels wrote about this: “Both of them never found out what was in their hands. The element, which was destined to revolutionize chemistry, disappeared in their hands without a trace ... It is therefore Lavoisier who actually discovered oxygen, and not the two who only described oxygen, without even knowing what they are describing. "

A detailed study of the properties of oxygen and its role in combustion and the formation of oxides led Lavoisier to the wrong conclusion that this gas is an acid-forming principle. In 1779 Lavoisier introduced the name for oxygen Oxygenium(from Greek"Oxide" - "sour" and "gennao" - I give birth ") -" giving birth to acids. "

"Oxidizing" element

Oxygen is a colorless (blue in a thick layer) gas, odorless and tasteless. It is slightly heavier than air and slightly soluble in water. When cooled to -183 ° C, oxygen turns into a mobile liquid of blue color, and at -219 ° C it freezes.

As befits an element that occupies a place in the upper right corner of the periodic table, oxygen is one of the most active non-metallic elements and has pronounced oxidizing properties. If I may say so, there is only one element more oxidizing than oxygen, fluorine. That is why liquid oxygen tanks - necessary accessory most liquid propellant rocket engines. A compound of oxygen was obtained even with such a chemically passive gas as xenon.

For the development of an active reaction of oxygen with most simple and complex substances, heating is necessary to overcome the potential barrier that prevents chemical process... With the help of catalysts that reduce the activation energy, the processes can proceed without heating, in particular, the combination of oxygen with hydrogen.

The high oxidizing ability of oxygen underlies the combustion of all types of fuel, including gunpowder, which do not require atmospheric oxygen to burn: during the combustion of such substances, oxygen is released from them.

The processes of slow oxidation of various substances at ordinary temperatures are no less important for life than combustion is for energy.

Slow oxidation of food substances in our body is the "energy base" of life. Let us note in passing that our body does not use inhaled oxygen very economically: there is about 16% oxygen in the exhaled air. The warmth of melting hay is the result of slow oxidation organic matter vegetable origin. Slow oxidation of manure and humus warms greenhouses.

Application: "sea of energy"

Oxygen is used in medical practice, and not only for pulmonary and heart diseases, when breathing is difficult. Subcutaneous oxygen administration was found to be effective remedy treatment of such serious diseases as gangrene, thrombophlebitis, elephantiasis, trophic ulcers.

It is no less important for industry... Air enrichment with oxygen makes many more efficient, faster, more economical technological processes, which are based on oxidation. And on such processes, almost all thermal energy is still supported. Converting cast iron to steel also impossible without oxygen. It is oxygen that "removes" excess carbon from cast iron. At the same time, the quality of the steel is also improved. I need oxygen in nonferrous metallurgy... Liquid oxygen serves rocket fuel oxidizer.

When hydrogen is burned in a stream of oxygen, a very ordinary substance is formed - H 2 O. Of course, for the sake of obtaining this substance, one should not be engaged in the combustion of hydrogen (which, by the way, is often obtained from water). The purpose of this process is different, it will be clear if the same reaction is written down in full, taking into account not only chemical products, but also the energy released during the reaction: H 2 + 0.5O 2 = H 2 O + 68317 calories.

Nearly seventy large calories per gram molecule! So you can get not only "sea of water", but also "sea of energy". For this, they receive water in jet engines operating on hydrogen and oxygen.

The same reaction is used for welding and cutting metals... True, in this region hydrogen can be replaced by acetylene. By the way, acetylene is produced on a large scale with the help of oxygen, in thermooxidative cracking processes: 6CH 4 + 4O 2 = C 2 H 2 + 8H 2 + 3CO + CO 2 + 3N 2 O.

This is just one example the use of oxygen in the chemical industry. Oxygen is needed for the production of many substances (suffice it to recall nitric acid), for gasification of coal, oil, fuel oil ...

Any porous combustible substance, for example, sawdust, being impregnated with a bluish cold liquid - liquid oxygen, becomes an explosive. Such substances are called oxyliquites and, if necessary, can replace dynamite in the development of ore deposits.

The world's annual production (and consumption) of oxygen is measured in millions of tons. Apart from the oxygen we breathe.

Oxygen production

Attempts to create a more or less powerful oxygen industry were made in the last century in many countries. But from the idea to the technical implementation there is often a "huge distance" ...

Especially fast development The oxygen industry began after Academician P.L. Kapitsa invented a turboexpander and the creation of powerful air separation units.

The easiest way to get oxygen is from air, since air is not a compound, and it is not that difficult to separate air. The boiling points of nitrogen and oxygen differ (at atmospheric pressure) at 12.8 ° C. Therefore, liquid air can be divided into components in rectification columns in the same way as, for example, oil is divided. But in order to turn the air into a liquid, it must be cooled to minus 196 ° C. We can say that the problem of getting oxygen is the problem of getting cold.

To get cold with ordinary air, the latter must be compressed, and then allowed to expand and at the same time make it perform mechanical work. Then, in accordance with the laws of physics, the air must be cooled. The machines in which this happens are called expander.

To obtain liquid air using piston expanders, pressures of the order of 200 atmospheres were needed. The efficiency of the installation was slightly higher than that of a steam engine. The installation turned out to be complicated, cumbersome, and expensive. In the late thirties, the Soviet physicist Academician P.L. Kapitsa proposed using a turbine as an expander. main feature The Kapitsa turbo expander is that the air in it expands not only in the nozzle apparatus, but also on the impeller blades. In this case, the gas moves from the periphery of the wheel to the center, working against centrifugal forces.

The turboexpander “makes” the cold using air compressed to just a few atmospheres. The energy that the expanding air gives off is not wasted, it is used to rotate the rotor of the electric current generator.

Modern installations for air separation, in which cold is obtained with the help of turbo expanders, give the industry, primarily metallurgy and chemistry, hundreds of thousands of cubic meters of gaseous oxygen.

What is oxygen? It is the 8th chemical element of D.I. Mendeleev, which has a relative atomic mass of 16. It is a colorless gas that has no odor and taste. Oxygen plays crucial role in people's lives. It is impossible to name the element that would be most important for the Earth. It's not just that we begin to study chemistry with oxygen. Oxygen forms some kind of compounds with all the elements of the periodic table. Light inert gases are an exception.

Oxygen, along with the chemical element "carbon", plays an essential role in the activities of mankind and life on Earth. In the Earth's atmosphere, it is in a free state. The oceans and seas contain a large amount of oxygen. Oxygen is "acid-generating." Under normal conditions, it is a gas composed of diatomic molecules. But oxygen also tends to solidify and condense into a light blue liquid. It can form explosive mixtures when interacting with flammable gases. In industry, oxygen is obtained by dividing air. Oxygen is used in some types of rocket fuel, in metallurgical plants, chemical plants, and in mines.

Prokaryotes, which are green-blue algae, had a great influence on the increase in oxygen volumes on the surface of our planet. These simplest organisms appeared about 2 billion years ago. They consumed carbon and oxygen from carbon dioxide, through photosynthesis, and at the same time released free oxygen into the air. Prokaryotes did not need free oxygen because they had an anaerobic breathing pattern. It turns out that the substance, without which we could not exist now, was once a polluting substance. Because of this pollution, significant changes have occurred in the structure of the Earth. Oxygen is a major cause of metal rusting and is also a strong oxidizing agent when heated. This chemical element is slightly soluble in water. At a temperature of 20 degrees Celsius, it has little chemical activity. Supports combustion of some substances in the open air. The simplest experience to check this phenomenon - ignition of an already smoldering wooden splinter in an oxygen atmosphere.

Historical facts about the chemical element Oxygen

Since ancient times, scientists have been interested in the processes of respiration and combustion. Chinese documents from the 8th century indicate that it is not the air itself that supports the combustion process, but only some of it. Leonardo Da Vinci, who lived in the 15th century, also investigated this phenomenon. The final discovery of the two components of air took place in 1773. Outstanding Swedish scientist K.V. Scheele and Joseph Priestley received oxygen almost simultaneously, independently of each other. Based on large-scale scientific research they were able to explain combustion and respiration as the processes of interaction of certain substances with Oxygen. And in 1775 A. Lavoisier called oxygen "acid-forming". This name was chosen because oxygen is part of some acids. The French scientist Pierre Bayenne made a significant contribution to the discovery of oxygen. He published his work on experiments with mercury and its oxide. Also here it is worth mentioning the theory of Phlogiston, which hindered the development of science for a long time.

In 1898, a statement was put forward that humanity in the near future is threatened with death from suffocation. This statement was due to the fact that a huge amount of carbon dioxide is released into the air every day, mainly from industrial factories and plants. Fortunately, this claim has been refuted. K.A. Timiryazev proved that green plants that emit oxygen will not allow humanity to disappear from this planet.

DEFINITION

Oxygen- chemical element with serial number 8. Located in the second period in the main subgroup of the VI-th group (in the short version of the periodic table) or in the 16th group according to modern numbering standards.

Atomic mass: 15.9994 amu

Electronic formula: 1s 2 2s 2 2p 4

Oxygen is the most abundant element in the earth's crust (47% of the mass). Marine and fresh water contain 85.82% (by weight) of bound oxygen. The free oxygen content in the atmosphere is 20.95% by volume and 23.10% by mass. Oxygen is part of the molecules of many organic substances. The number of oxygen atoms in living cells is about 25%, the mass fraction of oxygen in living organisms is about 65%.

Oxygen exists in the form of two-allotropic modifications - oxygen and ozone.

Oxygen(dioxygen) is a simple substance consisting of two oxygen atoms.

Formula: O 2.

Molar mass: 31.998 g / mol.

Oxygen under normal conditions is a colorless, tasteless and odorless gas. Oxygen is light blue in the liquid state, and light blue crystals in the solid.

Ozone- a simple substance consisting of three oxygen atoms.

Formula: O 3.

Structural formula:

Molar mass: 47.998 g / mol

Under normal conditions, ozone is a blue-blue gas with a characteristic pungent odor. In a liquid state, it is dark purple (indigo). In solid form - black crystals with a violet sheen.

Ozone is present in the atmosphere, in the so-called ozone layer, where it is formed from oxygen by ultraviolet radiation or lightning discharges:

Examples of problem solving

EXAMPLE 1

The task

The same amount of metal combines with 0.2 g of oxygen and 3.173 g of one of the halogens. Determine the halogen equivalent.

Solution

The equivalent of a substance is the amount that combines with 1 mole of hydrogen atoms or replaces the same number of hydrogen atoms in chemical reactions.

By the law of equivalents:

Equivalent mass of oxygen E О2 g / mol.

Let us express the equivalent mass of a halogen:

Halogen is iodine.

Answer

Halogen is iodine.

EXAMPLE 2

The task

The same amount of electricity was passed through the solutions. One of the cathodes released 25.9 g of lead. How many grams of nickel was released on the other cathode? How many liters of oxygen, measured under normal conditions, are released at each of the anodes?

Solution

Let us write down the equations of the processes occurring during the electrolysis of each solution.

Electrolysis of NiSO 4 solution

Ni 2+ + 2ē Ni 0 reduction of nickel ions

2Н 2 О - 4ē = О 2 + 4Н + oxidation with oxygen evolution

Electrolysis of PbSO 4 solution

Pb 2+ + 2ē Pb 0 reduction of nickel ions

2Н 2 О - 4ē = О 2 + 4Н + water oxidation with oxygen evolution

According to Faraday's law:

where I is the current strength during electrolysis, A; t is the duration of electrolysis, s; F is the Faraday number, F = 96500 C / mol, E Me is the equivalent mass of the metal.

Since the same amount of electricity was passed through the solutions of NiSO 4 and PbSO 4, then

The eighth chemical element in the periodic table - oxygen; his atomic mass is equal to 15.999. He is the most abundant element on Earth; in the atmosphere it is 21 percent, in the solid shell of the Earth - 47 percent; in the oceans - 86 percent.

Under normal conditions oxygen is a gas; the boiling point of liquefied oxygen is minus 182.9 degrees Celsius, and the transition temperature from solid to liquid is minus 218.7 degrees. In the air of the atmosphere, oxygen atoms combine into molecules; two atoms each. Known allotropic modification oxygen - ozone, the molecule of which consists of three atoms. Ozone occurs when exposed to ultraviolet radiation and when an electrical discharge (lightning) passes through.

Oxygen is chemically very reactive; in its activity, it is second only to fluorine. It connects with almost all elements, excluding inert gases. In compounds with metals, it exhibits variable and even fractional valence. Almost all reactions involving oxygen are of the exothermic type, that is, they occur with the release of heat or even light, and the combination with hydrogen occurs even in the form of an explosion. Ozone is even more active.

Of the oxygen compounds, the best known is water, the molecule of which consists of one oxygen atom and two hydrogen atoms; hydrogen is spaced apart in the molecule at an angle of 104.5 degrees. Water, better known as liquid, is the main part of into minerals, where it appears already in solid form. Liquid water boils at 100 degrees and freezes at zero degrees Celsius. In a liquid state, water has a low viscosity and high heat capacity. It is known that in a continuous mass, water molecules can dissociate, that is, disintegrate into their constituent atoms. Water is a good solvent.

With carbon, oxygen forms carbon dioxide, the molecule of which contains one carbon atom and two oxygen atoms; with a lack of oxygen, carbon monoxide, the molecule of which already contains one atom of one or another element.

Oxygen exhibits the greatest chemical activity in the composition of acids. He combines in them with nitrogen, sulfur, phosphorus and other elements; the molecules of acids are closed by hydrogen atoms. Aqueous solutions acids corrode almost all metals. Atomic oxygen also corrodes metals, forming oxides, but is less active.

The topology of the oxygen atom continues the same triangular theme that was started by the nitrogen atom: the original ring motor is deformed from three sides, the protrusions are extended, the cords are drawn closer; and the first stage of the formation of a three-pointed star with loops at the ends of the rays ends. In nitrogen, such a star remains flat for some time and in this form manages to find a similar one during this time and stick to it, forming a diatomic molecule.

The dimensions of the initial torus of the oxygen atom are somewhat larger: the nominal length of its cord is 29,400 ether balls, that is, 3700 balls longer than that of nitrogen; therefore, some correction of the topology of the atom occurs. Simultaneously with the elongation of the ends of the star, their convergence and twisting occurs; any two petals that have approached each other form another, secondary loop, and the third petal left alone turns around, creating an external suction groove, and covers it with its loop; this is the second intermediate stage in the topology of the oxygen atom.

At the third, last stage, the two petals that have approached each other first turn to each other "face", that is, with the suction sides, stick together as much as possible, and then bend over and rest against the tops of their loops against the suction groove of the wrapped single petal; this completes the topology of a single oxygen atom.

What happened in the end? And the result is a somewhat unique shape of the atom: with its contoured, outwardly open suction groove, it looks like a metal atom, but nevertheless it is not a metal; all its bent parts turn out to be tense, and for this reason they are unstable, and the atom pulsates, creating a standing thermal field around itself; it means that he is fluffy, and this fluffiness does not allow him to combine with the same atoms as himself and form a metal body. If it nevertheless connects with them, for example, during the formation of molecules, then this happens with the unbending of the paired petals and with the reversal of their loops, that is, with the rupture of the closed contour groove. It turns out that as long as the oxygen atom is alone, it is a metal, and when it combines with other atoms, it is no longer a metal.

The oxygen molecule consists of two atoms, united by sticking together the loops of paired petals and adjoining suction grooves. The molecule is also fluffy: the adhesion of atoms in it is counteracted by their single petals twisted like springs, and this opposition generates its pulsation, which is expressed in the fact that the adhered paired petals will periodically move out of the molecule - lengthening, and retract inward - shortening.

The combination of oxygen with hydrogen forms water: as a result of a strong thermal effect, the oxygen molecule breaks down into atoms; their released loops, not having time to turn around and stick together, are immediately filled with rings of hydrogen atoms; the famous molecule ash-two-o appears. The previously paired petals of the oxygen atom, after attaching hydrogen atoms to their loops, diverge at a certain angle and calm down. The whole molecule also calms down: despite the fact that the attached hydrogen atoms create additional fluffiness, in general, the pulsation of the water molecule turns out to be somewhat muffled, and under normal conditions it is no longer gaseous, but passes into a liquid.

Water differs from other liquids in many of its properties, and one of them is the constancy of viscosity with changes in temperature. If the molecules of other liquids, accelerating their thermal movements, reduce mutual contact and become, as it were, less attached to each other, then the water molecules retain their mutual connection practically constant; this is due to the fact that their mobility is mainly caused by the fluffiness of hydrogen atoms and bent single petals, and it depends very little on temperature. Of course, general thermal vibrations of molecules can make them fluffy to a gaseous state (this happens during boiling) or, conversely, reduce their mobility until mutual sliding stops (the phenomenon of formationice), but in the interval between these states, the bonds between the molecules with each other remain practically constant.

Water is also distinguished by its very high heat capacity. In a water molecule, the following absorbers of thermal movements can be distinguished: these are a single petal bent into a ring and two bent (straight) petals with hydrogen atoms at the ends. The pulsating ring of the bent lobe can have a wide range of amplitudes of its oscillations, that is, it can accumulate a lot of energy. But the main absorbers of thermal movements are still elongated petals; they are consoles with masses of hydrogen atoms assigned to their ends; the moment of inertia of these consoles is very large. Absorbing the energy of external shocks, the elongated petals only slightly increase the amplitude of their oscillations;and in order to rock them thoroughly, you need to apply a lot of external energy to them.

The explanation of other properties of water and oxygen, such as the ability to dissolve and oxidize, lies in the accumulation of more electrons by the oxygen atom and the water molecule as a whole. The atom has very long suction grooves facing outward; a lot of electrons can accumulate on such troughs. In a water molecule, additional external suction grooves arise along the contours of hydrogen atoms. Therefore, a water molecule can be considered an electron store.

A large accumulation of electrons is one of the reasons for the dissociation of water molecules: electrons, penetrating into the gaps under the hydrogen atoms, weaken their bonds with oxygen atoms up to their separation. Another reason is the thermal vibrations of the cantilever petals: the water molecule waves them like trees with its branches in strong wind; in the total mass of liquid, the molecules beat each other with these petals, like hammers; while the hydrogen atoms at the ends do not feel very comfortable.

In the same way, solids dissolve in water. First, having buried its cantilever petal in an atom (or molecule) of a solid, the water molecule injects electrons (syringes them); electrons weaken the interatomic bonds of a substance; and then with the blows of its petals, like cudgels, the water rips off fragile atoms and molecules from their places and absorbs them. Dissolution of oxygen-containing acids in water is accompanied by dissociation, that is, partial or complete separation of hydrogen atoms.

The oxidation of metals is approximately the same. First, by injection of electrons and blows of their petals, oxygen atoms dissolved in water weaken the attachment of surface metal atoms, and then envelop them with their petals like tentacles; in this case, the oxygen suction troughs are superimposed on the metal suction troughs and neutralize them. The oxygen in the composition of acids behaves in the same way with respect to the metal. They are connected to each other with the help of gutters, therefore their quantitative ratio is determined by the ratio of the lengths of the gutters, and it may not be multiple; hence - variable and fractional valence.

Enveloping atoms of various chemical elements with the help of tentacles (petals) of water, it helps to calm down the pulsations of its molecules: their vibrations are absorbed by neighboring atoms. Having lost their mobility, water molecules become a means of holding other atoms together, that is, an adhesive like nitrogen, like carbon, like boron or beryllium in a similar role. That is why there is so much water in the minerals.

Among the loop oxygen compounds, the formation of carbon monoxide and carbon dioxide can be distinguished. In the absence of oxygen, its atoms are first of all connected by their loops with the twisted loops of carbon atoms; its normally closed loops do not open at the same time; it's carbon monoxide. With an excess of oxygen and with high temperature closed loops of carbon also open and connect to loops of other oxygen atoms; carbon dioxide is produced. In these compounds, the strength of carbon and oxygen atoms decreases, that is, their potential energy decreases, and, accordingly, the kinetic energy increases, thermal energy... The rise in temperature is accompanied by the release of light: carbon atoms glow.

Of the three states of oxygen: atomic, molecular and ozone, the latter is the most active. If a single oxygen atom and a molecule have paired petals closed in their loops and not quite ready to attach to other atoms, then in ozone they are in a fragile connection with each other and easily open.

Four elements - "chalcogenes" (ie "giving birth to copper") head the main subgroup of the VI group (according to the new classification - the 16th group) periodic system... In addition to sulfur, tellurium and selenium, they also include oxygen. Let's take a closer look at the properties of this most common element on Earth, as well as the use and production of oxygen.

Element prevalence

IN bound form oxygen enters chemical composition water - its percentage is about 89%, as well as in the composition of the cells of all living things - plants and animals.

In air, oxygen is in a free state in the form of O2, occupying a fifth of its composition, and in the form of ozone - O3.

Physical properties

Oxygen O2 is a gas that is colorless, tasteless and odorless. It dissolves slightly in water. The boiling point is 183 degrees below zero Celsius. Oxygen is blue in liquid form and blue crystals in solid form. The melting point of oxygen crystals is 218.7 degrees below zero Celsius.

Chemical properties

When heated, this element reacts with many simple substances, both metals and non-metals, while forming the so-called oxides - compounds of elements with oxygen. into which the elements enter with oxygen is called oxidation.

For example,

4Na + О2 = 2Na2O

2. Through the decomposition of hydrogen peroxide when heated in the presence of manganese oxide, which acts as a catalyst.

3. Through the decomposition of potassium permanganate.

Oxygen production in industry is carried out in the following ways:

1. For technical purposes, oxygen is obtained from air, in which its usual content is about 20%, i. E. fifth part. To do this, air is first burned, obtaining a mixture with a liquid oxygen content of about 54%, liquid nitrogen - 44% and liquid argon - 2%. Then these gases are separated using a distillation process, using a relatively small interval between the boiling points of liquid oxygen and liquid nitrogen - minus 183 and minus 198.5 degrees, respectively. It turns out that nitrogen evaporates earlier than oxygen.

Modern equipment ensures the production of oxygen of any purity. Nitrogen, which is obtained during the separation of liquid air, is used as a raw material for the synthesis of its derivatives.

2. also gives oxygen of a very pure degree. This method has become widespread in countries with rich resources and cheap electricity.

Oxygen use

Oxygen is the most important element in the life of our entire planet. This gas, which is contained in the atmosphere, is consumed in the process by animals and people.

Obtaining oxygen is very important for such areas of human activity as medicine, welding and cutting of metals, blasting operations, aviation (for breathing people and for operating engines), metallurgy.

In the process of human economic activity, oxygen is consumed in large quantities- for example, when burning different types fuel: natural gas, methane, coal, wood. In all these processes, it is formed. At the same time, nature has provided for the process of natural binding of this compound through photosynthesis, which takes place in green plants under the influence of sunlight. As a result of this process, glucose is formed, which the plant then uses to build its tissues.