A diagram showing the content of gases in the air. Chemical composition of air and its hygienic importance

Young children often ask their parents about what air is and what it usually consists of. But not every adult can answer correctly. Of course, everyone studied the structure of air at school in natural history lessons, but over the years this knowledge could be forgotten. Let's try to make up for them.

What is Air?

Air is a unique “substance”. You can't see it, touch it, it's tasteless. This is why it is so difficult to give a clear definition of what it is. Usually they just say - air is what we breathe. It is around us, although we do not notice it at all. You can only feel it when a strong wind blows or an unpleasant odor appears.

What happens if the air disappears? Without it, not a single living organism can live or work, which means that all people and animals will die. It is indispensable for the breathing process. It is important how clean and healthy the air that everyone breathes is.

Where can I find fresh air?

The most beneficial air is found:

• In forests, especially pine ones.
• In the mountains.
• Near the sea.

The air in these places has a pleasant aroma and has beneficial properties for the body. This explains why children's health camps and various sanatoriums are located near forests, in the mountains or on the sea coast.

You can enjoy fresh air only away from the city. For this reason, many people buy summer cottages outside the locality. Some move to a temporary or permanent residence in the village and build houses there. Families with small children do this especially often. People are leaving because the air in the city is highly polluted.

Fresh air pollution problem

IN modern world The problem of environmental pollution is especially pressing. The work of modern factories, enterprises, nuclear power plants, and automobiles has a negative impact on nature. They emit harmful substances into the atmosphere that pollute the atmosphere. Therefore, very often people in urban areas experience a lack of fresh air, which is very dangerous.

Heavy air inside a poorly ventilated room is a serious problem, especially if it contains computers and other equipment. Being in such a place, a person may begin to suffocate from lack of air, develop pain in the head, and become weak.

According to statistics compiled by the World Health Organization, about 7 million human deaths per year are associated with the absorption of polluted air outdoors and indoors.

Harmful air is considered one of the main causes of such a terrible disease as cancer. This is what organizations involved in the study of cancer say.

Therefore, it is necessary to take preventive measures.

How to get fresh air?

A person will be healthy if he can breathe fresh air every day. If it is not possible to move out of town due to important work, lack of money or for other reasons, then you need to look for a way out of the situation on the spot. In order for the body to receive the necessary amount of fresh air, the following rules should be followed:

1. Be outside more often, for example, take evening walks in parks and gardens.
2. Go for a walk in the forest on weekends.
3. Constantly ventilate living and working areas.
4. Plant more green plants, especially in offices where there are computers.
5. It is advisable to visit resorts located by the sea or in the mountains once a year.

What gases does air consist of?

Every day, every second, people inhale and exhale without thinking about the air at all. People do not react to him in any way, despite the fact that he surrounds them everywhere. Despite its weightlessness and invisibility to the human eye, air has a rather complex structure. It involves the interrelation of several gases:

• Nitrogen.
• Oxygen.
• Argon.
• Carbon dioxide.
• Neon.
• Methane.
• Helium.
• Krypton.
• Hydrogen.
• Xenon.

The main share of air is occupied nitrogen , the mass fraction of which is 78 percent. 21 percent of the total is oxygen - the most essential gas for human life. The remaining percentage is occupied by other gases and water vapor, from which clouds are formed.

The question may arise, why is there so little oxygen, just a little more than 20%? This gas is reactive. Therefore, with an increase in its share in the atmosphere, the likelihood of fires in the world will increase significantly.

What is the air we breathe made of?

The two main gases that make up the air we breathe every day are:

• Oxygen.
• Carbon dioxide.

We inhale oxygen, exhale carbon dioxide. Every schoolchild knows this information. But where does oxygen come from? The main source of oxygen production is green plants. They are also consumers of carbon dioxide.

The world is interesting. In all life processes, the rule of maintaining balance is observed. If something went from somewhere, then something came from somewhere. Same with air. Green spaces produce the oxygen that humanity needs to breathe. Humans consume oxygen and release carbon dioxide, which in turn feeds plants. Thanks to this system of interaction, life exists on planet Earth.

Knowing what the air we breathe consists of and how much it is polluted in modern times, it is necessary to protect the plant world of the planet and do everything possible to increase the number of green plants.

Video about air composition

Every day we take about 20 thousand breaths. It is enough to stop the flow of oxygen into the blood for 7–8 minutes for irreversible changes to occur in the cerebral cortex. Air supports many biochemical reactions in our body. And our health largely depends on its quality.

text: Tatyana Gaverdovskaya

Every day we take about 20 thousand breaths. It is enough to stop the flow of oxygen into the blood for 7-8 minutes for irreversible changes to occur in the cerebral cortex. Air supports many biochemical reactions in our body. And our health largely depends on its quality.

Atmospheric air at the Earth's surface normally consists of nitrogen (78.09%), oxygen (20.95%), and carbon dioxide (0.03-0.04%). The remaining gases together occupy less than 1% by volume, these include argon, xenon, neon, helium, hydrogen, radon and others. However, emissions industrial enterprises and transport violate this ratio of components. In Moscow alone, from 1 to 1.2 million tons of harmful emissions are emitted into the air. chemical substances per year, that is, 100-150 kg for each of the 12 million residents of Moscow. It’s worth thinking about what we breathe and what can help us resist this “gas attack.”

Shortest way

The human lungs have a surface area of ​​up to 100 m2, which is 50 times greater than the area of ​​the skin. In them, the air is in direct contact with the blood, in which almost all of the substances contained in it dissolve. From the lungs, bypassing the detoxification organ - the liver, they act on the body 80-100 times stronger than through the gastrointestinal tract when swallowed.

The air we breathe is polluted by about 280 toxic compounds. These are salts of heavy metals (Cu, Cd, Pb, Mn, Ni, Zn), oxides of nitrogen and carbon, ammonia, sulfur dioxide, etc. In calm weather, all these harmful compounds settle and create a dense layer near the ground - smog. Under the influence of ultraviolet rays during the hot period, harmful gas mixtures are converted into more harmful substances - photooxidants. Every day a person inhales up to 20 thousand liters of air. And in a month big city may reach a toxic dose. As a result, immunity decreases and respiratory and neurological diseases occur. Children especially suffer from this.

We are taking action

1. Tea made from calendula, chamomile, sea buckthorn and rose hips will help protect the body from the penetration of heavy metals into cells.

2. Some plants, for example, coriander (cilantro), are successfully used to remove toxic substances. According to experts, you need to eat at least 5 g of this plant per day (about 1 tsp).

3. Garlic, sesame seeds, ginseng and many other plant products also have the ability to bind and remove heavy metals. Also effective Apple juice, which contains a lot of pectins - natural adsorbents.

City without oxygen

Residents of the metropolis constantly experience a lack of oxygen due to industrial emissions and pollution. Thus, when burning 1 kg of coal or firewood, more than 2 kg of oxygen is consumed. One car absorbs as much oxygen in 2 hours of operation as a tree releases in 2 years.

The oxygen concentration in the air is often only 15-18%, while the norm is about 20%. At first glance, this is a small difference - only 3-5%, but for our body it is quite noticeable. Oxygen levels in the air of 10% or below are lethal to humans. Unfortunately, there is not enough oxygen in natural conditions exists only in city parks (20.8%), suburban forests (21.6%) and on the shores of seas and oceans (21.9%). The situation is aggravated by the fact that every 10 years the area of ​​the lungs decreases by 5%.

Oxygen increases mental ability, the body's resistance to stress, stimulates the coordinated work of internal organs, improves immunity, promotes weight loss, and normalizes sleep. Scientists have calculated that if there were 2 times more oxygen in the Earth's atmosphere, we could run hundreds of kilometers without getting tired.

Oxygen makes up 90% of the mass of a water molecule. The body contains 65-75% water. The brain makes up 2% of the total body weight and consumes 20% of the oxygen entering the body. Without oxygen, cells do not grow and die.

We are taking action

1. To adequately saturate the body with oxygen, you need to walk in the forest for at least one hour every day. Over the course of one year, a typical tree produces the amount of oxygen required for a family of 4 people over the same period.

2. To replenish the oxygen deficiency in the body, doctors recommend drinking salted and mineral alkaline water, lactic acid drinks ( skimmed milk, whey), juices.

3. Oxygen cocktails help get rid of hypoxia. In terms of its effect on the body, a small portion of a cocktail is equivalent to a full-fledged walk in the forest.

4. Oxygen therapy is a treatment method based on breathing a gas mixture with an increased (relative to the oxygen content in the air) oxygen concentration.

Home trap

According to WHO experts, city dwellers spend about 80% of their time indoors. Scientists have found that indoor air is 4-6 times dirtier than outside air and 8-10 times more toxic. These are formaldehyde and phenol from furniture, some types of synthetic fabrics, carpeting, harmful substances from building materials (for example, carbamide from cement can release ammonia), dust, pet hair, etc. At the same time, in urban areas oxygen is significantly less, which leads to oxygen deficiency (hypoxia) in people.

A gas stove can also negatively affect the atmosphere in the house. The air of gasified buildings, in comparison with outside air, contains 2.5 times more harmful nitrogen oxides, 50 times more sulfur-containing substances, phenol - by 30-40%, carbon oxides - by 50-60%.

But the main scourge of indoor spaces is carbon dioxide, the main source of which is humans. We exhale from 18 to 25 liters of this gas per hour. Recent studies by foreign scientists have shown that carbon dioxide negatively affects the human body even in low concentrations. In residential premises, carbon dioxide should not exceed 0.1%. In a room with a carbon dioxide concentration of 3-4%, a person suffocates, headaches, tinnitus appear, and the pulse slows down. However, in small quantities (0.03-0.04%) carbon dioxide is necessary to maintain physiological processes.

We are taking action

1. It is very important that the air in the room is “light”, i.e. ionized. With a decrease in the number of air ions, oxygen is less absorbed by red blood cells, and hypoxia is possible. The air of cities contains only 50-100 light ions per 1 cm³, and tens of thousands of heavy (uncharged) ions. In the mountains the highest air ionization is 800-1000 per 1 cm³ or more.

2. According to a study conducted by the US space agency, some houseplants act as effective biofilters. Chlorophytum and nephrolepis fern help in the fight against formaldehyde. Xylene and toluene, which are released, for example, by varnishes, are neutralized by Ficus Benjamin. Azalea can cope with ammonia compounds. Sansevieria, philodendron, ivy, and dieffenbachia produce a lot of oxygen and absorb harmful substances.

3. Don’t forget about regular ventilation. This is especially important in the bedroom, where people spend a third of their lives.

Dangers on the road

Motor transport supplies the lion's share of air pollutants: for Moscow it is about 93%, for St. Petersburg - 71%. There are almost 4 million cars in Moscow, and their number is growing every year. By 2015, experts believe that Moscow's vehicle fleet will amount to more than 5 million vehicles. In a month, the average passenger car burns as much oxygen as 1 hectare of forest produces in a year, while annually releasing approximately 800 kg of carbon monoxide, about 40 kg of nitrogen oxides and about 200 kg of various hydrocarbons.

The most serious danger for those who frequently use cars is carbon monoxide. It binds to blood hemoglobin 200 times faster than oxygen. Experiments conducted in the USA showed that due to the influence of carbon monoxide, people who spend a lot of time driving have impaired reaction. At a carbon monoxide concentration of 6 mg/m3 for 20 minutes, the color and light sensitivity of the eyes decreases. Under the influence of large amounts of carbon monoxide, fainting, coma, and even death can occur.

We are taking action

1. Lactic enzymes and acids remove carbon monoxide breakdown products. With normal tolerance, you can drink up to a liter of milk per day.

2. To neutralize the effects of carbon monoxide, it is recommended to eat as many fruits as possible: green apples, grapefruits, as well as honey and walnuts.

Kind with healthy

German scientists have found that sexual arousal activates the cardiovascular system and increases blood flow. As a result, tissues are better saturated with oxygen and the risk of heart attack or stroke is reduced by 50%.

What does the metro breathe?

Scientists from the Karolinska Institute in Sweden have concluded that more than 5 thousand Swedes die every year from inhaling microscopic particles of coal, asphalt, iron and other pollutants in the air of the Stockholm metro. These particles have a stronger destructive effect on human DNA than particles contained in car exhaust and formed as a result of burning wood fuel.

Sky over Moscow

According to Roshydromet observations, in 2011 the degree of air pollution in the cities of the Moscow region was assessed as: very high - in Moscow, high - in Serpukhov, increased - in Voskresensk, Klin, Kolomna, Mytishchi, Podolsk and Elektrostal, low - in Dzerzhinsky, Shchelkovo and Prioksko-Terrasny biosphere reserve.

The chemical composition of air is important hygienic value, since it plays a decisive role in the respiratory function of the body. Atmospheric air is a mixture of oxygen, carbon dioxide, argon and other gases in the ratios given in table. 1.

Oxygen(O2) is the most important component of air for humans. At rest, a person usually absorbs an average of 0.3 liters of oxygen per minute.

During physical activity, oxygen consumption increases sharply and can reach 4.5/5 liters or more per minute. Fluctuations in the oxygen content in atmospheric air are small and, as a rule, do not exceed 0.5%.

In residential, public and sports premises, no significant changes in oxygen content are observed, since outside air penetrates into them. Under the most unfavorable hygienic conditions in the room, a decrease in oxygen content of 1% was noted. Such fluctuations do not have significant influence on the body.

Typically, physiological changes are observed when the oxygen content decreases to 16-17%. If its content decreases to 11-13% (when rising to a height), pronounced oxygen deficiency appears, a sharp deterioration in well-being and a decrease in performance. Oxygen content up to 7-8% can be fatal.

In sports practice, oxygen inhalation is used to increase performance and intensity of recovery processes.

Carbon dioxide(CO2), or carbon dioxide, is a colorless, odorless gas formed during the breathing of people and animals, rotting and decomposition of organic substances, combustion of fuel, etc. In atmospheric air outside settlements The carbon dioxide content averages 0.04%, and in industrial centers its concentration rises to 0.05-0.06%. In residential and public buildings, when there are a large number of people in them, the carbon dioxide content can increase to 0.6-0.8%. Under the worst hygienic conditions in a room (large crowds of people, poor ventilation, etc.), its concentration usually does not exceed 1% due to the penetration of outside air. Such concentrations do not cause negative effects in the body.

With prolonged inhalation of air containing 1-1.5% carbon dioxide, a deterioration in health is noted, and at 2-2.5% pathological changes are detected. Significant disruption of body functions and decreased performance occur when the carbon dioxide content is 4-5%. At levels of 8-10%, loss of consciousness and death occur. A significant increase in the content of carbon dioxide in the air can occur during emergency situations in confined spaces (mines, mines, submarines, bomb shelters, etc.) or in places where intensive decomposition of organic substances occurs.

Determining the carbon dioxide content in residential, public and sports facilities can serve as an indirect indicator of air pollution from human waste products. As already noted, carbon dioxide itself in these cases does not cause harm to the body, however, along with an increase in its content, a deterioration in the physical and chemical properties of the air is observed (temperature and humidity increase, the ionic composition is disrupted, foul-smelling gases appear). Indoor air is considered to be of poor quality if the carbon dioxide content in it exceeds 0.1%. This value is accepted as a calculated value when designing and installing ventilation in rooms.

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Chemical composition of air is important in the implementation of respiratory function. Atmospheric air is a mixture of gases: oxygen, carbon dioxide, argon, nitrogen, neon, krypton, xenon, hydrogen, ozone, etc. Oxygen is the most important. At rest, a person absorbs 0.3 l/min. During physical activity, oxygen consumption increases and can reach 4.5–8 l/min. Fluctuations in the oxygen content in the atmosphere are small and do not exceed 0.5%. If the oxygen content decreases to 11-13%, symptoms of oxygen deficiency appear.

Oxygen content of 7-8% can lead to death. Carbon dioxide is colorless and odorless, formed during respiration and decay, combustion of fuel. In the atmosphere it is 0.04%, and in industrial zones – 0.05-0.06%. With a large crowd of people it can increase to 0.6 - 0.8%. With prolonged inhalation of air containing 1-1.5% carbon dioxide, a deterioration in health is noted, and with 2-2.5% - pathological changes. At 8-10% loss of consciousness and death, the air has a pressure called atmospheric or barometric. It is measured in millimeters of mercury (mmHg), hectopascals (hPa), millibars (mb). Normal atmospheric pressure is considered to be at sea level at a latitude of 45˚ at an air temperature of 0˚C. It is equal to 760 mmHg. (The air in a room is considered to be of poor quality if it contains 1% carbon dioxide. This value is accepted as a calculated value when designing and installing ventilation in rooms.

Air pollution. Carbon monoxide is a colorless and odorless gas that is formed during incomplete combustion of fuel and enters the atmosphere with industrial emissions and exhaust gases from internal combustion engines. In megacities, its concentration can reach 50-200 mg/m3. When smoking tobacco, carbon monoxide enters the body. Carbon monoxide is a blood and general toxic poison. It blocks hemoglobin, it loses its ability to carry oxygen to tissues. Acute poisoning occurs when the concentration of carbon monoxide in the air is 200-500 mg/m3. In this case, headache, general weakness, nausea, and vomiting are observed. The maximum permissible average daily concentration is 0 1 mg/m3, one-time – 6 mg/m3. The air can be polluted by sulfur dioxide, soot, tarry substances, nitrogen oxides, and carbon disulfide.

Microorganisms. They are always found in small quantities in the air, where they are carried with soil dust. Microbes of infectious diseases entering the atmosphere quickly die. The air in residential premises and sports facilities poses a particular danger in terms of epidemiology. For example, in wrestling halls there is a microbial content of up to 26,000 per 1m3 of air. Aerogenic infections spread very quickly in such air.

Dust It is light dense particles of mineral or organic origin; when dust gets into the lungs, it lingers there and causes various diseases. Industrial dust (lead, chrome) can cause poisoning. In cities, dust should not exceed 0.15 mg/m3. Sports grounds must be regularly watered, have a green area, and carry out wet cleaning. Sanitary protection zones have been established for all enterprises that pollute the atmosphere. In accordance with the hazard class, they have different sizes: for enterprises of class 1 - 1000 m, 2 - 500 m, 3 - 300 m, 4 -100 m, 5 - 50 m. When placing sports facilities near enterprises, it is necessary to take into account the wind rose, sanitary protective zones, degree of air pollution, etc.

One of the important measures to protect the air environment is preventive and ongoing sanitary supervision and systematic monitoring of the state of atmospheric air. It is carried out using an automated monitoring system.

Clean atmospheric air at the surface of the Earth has the following chemical composition: oxygen - 20.93%, carbon dioxide - 0.03-0.04%, nitrogen - 78.1%, argon, helium, krypton 1%.

The exhaled air contains 25% less oxygen and 100 times more carbon dioxide.
Oxygen. The most important component of air. It ensures the flow of redox processes in the body. An adult at rest consumes 12 liters of oxygen, with physical work 10 times more. In the blood, oxygen is bound to hemoglobin.

Ozone. A chemically unstable gas, it is capable of absorbing solar short-wave ultraviolet radiation, which has a detrimental effect on all living things. Ozone absorbs long-wave infrared radiation emanating from the Earth, and thereby prevents its excessive cooling (the Earth's ozone layer). Under the influence of ultraviolet radiation, ozone decomposes into an oxygen molecule and an atom. Ozone is a bactericidal agent for water disinfection. In nature, it is formed during electrical discharges, during the evaporation of water, during ultraviolet radiation, during a thunderstorm, in the mountains and in coniferous forests.

Carbon dioxide. It is formed as a result of redox processes occurring in the body of people and animals, combustion of fuel, and decay of organic substances. In the air of cities, the concentration of carbon dioxide is increased due to industrial emissions - up to 0.045%, in residential premises - up to 0.6-0.85. An adult at rest emits 22 liters of carbon dioxide per hour, and during physical work - 2-3 times more. Signs of deterioration in a person’s health appear only with prolonged inhalation of air containing 1-1.5% carbon dioxide, pronounced functional changes - at a concentration of 2-2.5% and pronounced symptoms (headache, general weakness, shortness of breath, palpitations, decreased performance) – at 3-4%. The hygienic importance of carbon dioxide lies in the fact that it serves as an indirect indicator of general air pollution. The carbon dioxide standard in gyms is 0.1%.

Nitrogen. An indifferent gas serves as a diluent for other gases. Increased inhalation of nitrogen can have a narcotic effect.

Carbon monoxide. Formed during incomplete combustion of organic substances. It has neither color nor smell. The concentration in the atmosphere depends on the intensity of vehicle traffic. Penetrating through the pulmonary alveoli into the blood, it forms carboxyhemoglobin, as a result of which hemoglobin loses its ability to carry oxygen. The maximum permissible average daily concentration of carbon monoxide is 1 mg/m3. Toxic doses of carbon monoxide in the air are 0.25-0.5 mg/l. With prolonged exposure, headache, fainting, palpitations.

Sulphur dioxide. It enters the atmosphere as a result of burning fuel rich in sulfur (coal). It is formed during the roasting and melting of sulfur ores and during the dyeing of fabrics. It irritates the mucous membranes of the eyes and upper respiratory tract. The sensation threshold is 0.002-0.003 mg/l. The gas has a harmful effect on vegetation, especially coniferous trees.
Mechanical air impurities come in the form of smoke, soot, soot, crushed soil particles and other solids. Air dust content depends on the nature of the soil (sand, clay, asphalt), its sanitary condition (watering, cleaning), air pollution from industrial emissions, and the sanitary condition of the premises.

Dust mechanically irritates the mucous membranes of the upper respiratory tract and eyes. Systematic inhalation of dust causes respiratory diseases. When breathing through the nose, up to 40-50% of dust is retained. Microscopic dust that remains suspended for a long time is the most unfavorable from a hygienic point of view. The electrical charge of dust enhances its ability to penetrate and linger in the lungs. Dust. containing lead, arsenic, chromium and other toxic substances, causes typical poisoning phenomena, and when penetrated not only by inhalation, but also through the skin and gastrointestinal tract. In dusty air, the intensity of solar radiation and air ionization are significantly reduced. To prevent the adverse effects of dust on the body, residential buildings are located on the windward side of air pollutants. Sanitary protection zones with a width of 50-1000 m or more are arranged between them. In residential premises, systematic wet cleaning, ventilation of premises, change of shoes and outerwear, in open areas, use non-dusting soils and watering.

Air microorganisms. Bacterial pollution of air, as well as other environmental objects (water, soil), poses an epidemiological danger. There are various microorganisms in the air: bacteria, viruses, molds, yeast cells. The most common is the airborne method of transmission of infections: a large number of microbes enter the air and enter the air when inhaled. Airways healthy people. For example, during a loud conversation, and even more so when coughing and sneezing, tiny droplets are sprayed over a distance of 1-1.5 m and spread with air over 8-9 m. These droplets can be suspended for 4-5 hours, but in most cases settle in 40-60 minutes. In dust, the influenza virus and diphtheria bacilli remain viable for 120-150 days. There is a well-known relationship: the more dust in indoor air, the more abundant the microflora content in it.

Chemical composition of air

Air is a mixture of gases that form a protective layer around the Earth - the atmosphere. Air is necessary for all living organisms: animals for breathing, and plants for nutrition. In addition, air protects the Earth from the harmful ultraviolet radiation of the Sun. The main components of air are nitrogen and oxygen. The air also contains small admixtures of noble gases, carbon dioxide and a certain amount of solid particles - soot and dust. All animals need air to breathe. About 21% of air is oxygen. An oxygen molecule (O2) consists of two bonded oxygen atoms.

Air composition

The percentage of various gases in the air varies slightly depending on location, time of year and day. Nitrogen and oxygen are the main components of air. One percent of the air consists of noble gases, carbon dioxide, water vapor and pollutants such as nitrogen dioxide. Gases contained in air can be separated by fractional distillation. The air is cooled until the gases become liquid (see the article “Solids, Liquids and Gases”). After this, the liquid mixture is heated. Each liquid has its own boiling point, and the gases formed during boiling can be collected separately. Oxygen, nitrogen and carbon dioxide constantly enter living organisms from the air and return to the air, i.e. a cycle occurs. Animals inhale oxygen from the air and exhale carbon dioxide.

Oxygen

Oxygen is essential for life. Animals breathe it, use it to digest food and get energy. During the day, a process occurs in plants photosynthesis, and plants release oxygen. Oxygen is also necessary for combustion; Without oxygen, nothing can burn. Almost 50% of the compounds in the earth's crust and oceans contain oxygen. Ordinary sand is a compound of silicon and oxygen. Oxygen is used in breathing apparatus for divers and in hospitals. Oxygen is also used in steel production (see article "Iron, steel and other materials") and rocketry (see article "Rockets and spacecraft").

In the upper layers of the atmosphere, oxygen atoms combine in threes to form the ozone molecule (O3). Ozone is an allotropic modification of oxygen. Ozone is a poisonous gas, but in the atmosphere the ozone layer protects our planet by absorbing most harmful ultraviolet radiation from the Sun (for more details, see the article “Impact of the Sun on the Earth”).

Nitrogen

More than 78% of air is nitrogen. Proteins, from which living organisms are built, also contain nitrogen. The main industrial application of nitrogen is ammonia production needed for fertilizers. To do this, nitrogen is combined with hydrogen. Nitrogen is pumped into packaging for meat or fish, because... upon contact with ordinary air, products oxidize and deteriorate. Human organs intended for transplantation are stored in liquid nitrogen because it is cold and chemically inert. A nitrogen (N2) molecule consists of two bonded nitrogen atoms.

Plants obtain nitrogen from the soil in the form of nitrates and use it to synthesize proteins. Animals eat plants, and nitrogen compounds are returned to the soil through animal excretions and when their dead bodies decompose. In the soil, nitrogen compounds are decomposed by bacteria, releasing ammonia and then free nitrogen. Other bacteria absorb nitrogen from the air and convert it into nitrates for use by plants.

Carbon dioxide

Carbon dioxide is a compound of carbon and oxygen. The air contains about 0.003% carbon dioxide. A carbon dioxide (CO2) molecule consists of two oxygen atoms and one carbon atom. Carbon dioxide is one of the elements of the carbon cycle. Plants absorb it during photosynthesis, and animals exhale it. Carbon dioxide is also produced by the combustion of substances containing carbon, such as wood or gasoline. Because our cars and factories burn so much fuel, the proportion of carbon dioxide in the atmosphere is increasing. Most substances cannot burn in carbonic acid gas, which is why it is used in fire extinguishers. Carbon dioxide is denser than air. It “smothers” the flame, cutting off the access of oxygen. Carbon dioxide dissolves slightly in water, forming a weak solution of carbonic acid. Solid carbon dioxide is called dry ice. When dry ice melts, it turns into gas; it is used to create artificial clouds in the theater.

Air pollution

Soot and poisonous gases - carbon monoxide, nitrogen dioxide, sulfur dioxide - pollute the atmosphere. Carbon monoxide is formed during combustion. Many substances burn so quickly that they do not have time to add enough oxygen and instead of carbon dioxide (CO2), carbon monoxide (CO) is formed. Carbon monoxide is very poisonous; it prevents the animals' blood from carrying oxygen. There is only one oxygen atom in a carbon monoxide molecule. Car exhaust contains carbon monoxide as well as nitrogen dioxide, which causes acid rain. Sulfur dioxide is released when fossil fuels, especially coal, are burned. It is poisonous and makes breathing difficult. In addition, it dissolves in water and causes acid rain. Dust and soot particles emitted into the atmosphere by enterprises also pollute the air; we inhale them, they settle on plants. Lead is added to gasoline for better combustion (however, many cars now run on lead-free gasoline). Lead compounds accumulate in the body and have a detrimental effect on nervous system. In children they can cause brain damage.

Acid rain

Rainwater always contains a little acid due to dissolved carbon dioxide, but pollutants (sulfur and nitrogen dioxides) increase the acidity of the rain. Acid rain causes corrosion of metals, corrodes stone structures and increases the acidity of fresh water.

Noble gases

Noble gases are 6 elements of group 8 of the periodic table. They are extremely chemically inert. Only they exist in the form of individual atoms that do not form molecules. Because of their passivity, some of them are used to fill lamps. Xenon is practically not used by humans, but argon is pumped into light bulbs, and fluorescent lamps are filled with creep tone. Neon flashes red-orange when electrically charged. It is used in sodium street lamps and neon lamps. Radon is radioactive. It is formed by the decay of the metal radium. No helium compounds are known to science, and helium is considered completely inert. Its density is 7 times less than the density of air, which is why airships are filled with it. Helium filled Balloons equipped with scientific equipment and launched into the upper atmosphere.

Greenhouse effect

This is the name for the currently observed increase in carbon dioxide content in the atmosphere and the resulting global warming, i.e. increase in average annual temperatures around the world. Carbon dioxide prevents heat from leaving the Earth, just as glass maintains high temperatures inside a greenhouse. As there is more carbon dioxide in the air, more heat is trapped in the atmosphere. Even slight warming causes sea levels to rise, winds to change and some of the ice at the poles to melt. Scientists believe that if the carbon dioxide content increases as quickly, then in 50 years the average temperature could increase by 1.5°C to 4°C.

air is a mixture of gases, and therefore elements. . Nitrogen, oxygen, carbon dioxide. There are other gases in cities...

Percentage of gases.

do you need a graphical representation of an air molecule?

Air in chemistry - NO2

zit hain. Allah Akbar. takbir foreign words that are forbidden to be spoken. what is this for - HZ

If you think that air has its own separate formula, you are mistaken; in chemistry it is not designated in any way.

Air is the natural mixture of gases, mainly nitrogen and oxygen, that makes up the earth's atmosphere. Air composition: Nitrogen N2 Oxygen O2 Argon Ar Carbon dioxide CO2 Neon Ne Methane CH4 Helium He Krypton Kr Hydrogen H2 Xenon Xe Water H2O In addition, air always contains water vapor. So, at a temperature of 0 °C, 1 m³ of air can hold a maximum of 5 grams of water, and at a temperature of +10 °C - already 10 grams. In alchemy, air is symbolized as a triangle with a horizontal line.

nitrogen

we inhale the main component. air

Alternative descriptions

Gas that makes metal brittle

A gas that makes up 78% air

Main "air filler"

The main component of the air you breathe, which is pure form you can't breathe

Air Component

Fertilizer in the air

Chemical element - the basis of a number of fertilizers

Chemical element, one of the main plant nutrients

Chemical element, component of air

Nitrogenium

Liquid refrigerant

Chemical element, gas

Magic sword of Paracelsus

In Latin, this gas is called “nitrogenium”, that is, “giving birth to saltpeter”

The name of this gas comes from the Latin word for lifeless.

This gas, a component of air, was practically absent from the Earth's primary atmosphere 4.5 billion years ago.

A gas whose liquid is used to cool ultra-precision instruments

What gas is in liquid state stored in a Dewar flask?

The gas that froze Terminator II

Gas cooler

What gas extinguishes fire?

Most abundant element in the atmosphere

Base of all nitrates

Chemical element, N

Freezing Gas

Three quarters air

Contains ammonia

Gas from air

Gas number 7

Element from saltpeter

The main gas in the air

The most popular gas

Element from nitrates

Liquid gas from a vessel

No. 1 gas in the atmosphere

Fertilizer in the air

78% air

Gas for cryostat

Almost 80% air

Most popular gas

Diffuse gas

Gas from a Dewar flask

Main component of air

. "N" in the air

Nitrogen

Air component

An ancient rich Philistine city, with the Temple of Dagon

Much of the atmosphere

Dominates the air

Following carbon in the table

Between carbon and oxygen in the table

7th by Mendeleev

Before oxygen

Oxygen precursor in table

Harvest gas

. "lifeless" among gases

Following carbon in the table

Dog from Fet's palindrome

Gas is a component of fertilizers

Up to oxygen in the table

After carbon in the table

78.09% air

What gas is more in the atmosphere?

What gas is in the air?

Gas that occupies most of the atmosphere

Seventh in the ranks of chemical elements

element No. 7

Component of air

In the table it is after carbon

Non-vital part of the atmosphere

. "giving birth to saltpeter"

The oxide of this gas is the “intoxicating gas”

The basis of the earth's atmosphere

Most of the air

Part of the air

Carbon successor in table

Lifeless part of the air

Seventh in the Mendeleev order

Gas in air

Bulk air

Seventh chemical element

About 80% air

Gas from the table

Gas that significantly affects the yield

Main component of nitrates

Air base

Main element of air

. "non-life" element of air

Mendeleev appointed him seventh

The lion's share of air

Seventh in the Mendeleev line

Main gas in the air

Seventh in the chemical order

Main gas air

Main air gas

Between carbon and oxygen

Diatomic gas inert under normal conditions

The most common gas on Earth

Gas, the main component of air

Chemical element, colorless and odorless gas, the main component of air, which is also part of proteins and nucleic acids

Name of chemical element

. "N" in the air

. "Lifeless" among gases

. The "non-life" element of air

. "Giving birth to saltpeter"

7th Count Mendeleev

Most of the air we breathe

Part of the air

Gas is a component of fertilizers

Gas that significantly affects crop yield

Home composition. part of the air

Main part of air

Main "air filler"

The oxide of this gas is the "intoxicating gas"

What gas is more in the atmosphere?

What liquid gas is stored in a Dewar flask?

What gas is in the air?

What gas extinguishes fire?

M. chemical. base, main element of saltpeter; saltpeter, saltpeter, saltpeter; it is also the main, in quantity, component of our air (nitrogen volume, oxygen Nitrogenous, nitrogenous, nitrogenous, containing nitrogen. Chemists distinguish with these words the measure or degree of nitrogen content in its combinations with other substances

In Latin this gas is called "nitrogenium", that is, "giving birth to saltpeter"

The name of this gas comes from the Latin word for lifeless.

Before oxygen in the table

The last carbon in the table

Seventh Count of Mendeleev

Chemical element with code name 7

Chemical element

What is chemical element No. 7

Included in saltpeter

Natural chemical composition of atmospheric air

In terms of chemical composition, pure atmospheric air is a mixture of gases: oxygen, carbon dioxide, nitrogen, as well as a number of inert gases (argon, helium, krypton, etc.). Since air is a physical mixture, and not a chemical compound of its constituent gases, when rising even tens of kilometers, the percentage of these gases practically does not change.

However, with height, as a result of a decrease in atmospheric density, the concentrations and partial pressure of all gases in the air decrease.

At the Earth's surface the atmospheric air contains:

oxygen – 20.93%;

nitrogen – 78.1%;

carbon dioxide – 0.03-0.04%;

inert gases – from 10-3 to 10-6%.

Oxygen (O2)- the most important part of air for life. It is necessary for oxidative processes and is found in the blood, mainly in a bound state - in the form of oxyhemoglobin, which is transported by red blood cells to the cells of the body.

The transition of oxygen from alveolar air to blood occurs due to the difference in partial pressure in alveolar air and venous blood. For the same reason, oxygen flows from arterial blood into the interstitial fluid, and then into the cells.

In nature, oxygen is spent mainly on the oxidation of organic substances contained in air, water, soil and combustion processes. The loss of oxygen is replenished due to its large reserves in the atmosphere, as well as as a result of the activity of phytoplankton in the oceans and land plants. Continuous turbulent flows of air masses equalize the oxygen content in the surface layer of the atmosphere. Therefore, the oxygen level at the Earth's surface fluctuates slightly: from 20.7 to 20.95%. In residential premises and public buildings, the oxygen content also remains virtually unchanged due to its easy diffusion through the pores of building materials, cracks in windows, etc.

In sealed rooms (shelters, submarines, etc.), the oxygen content can decrease significantly. However, a pronounced deterioration in well-being and a decrease in performance in people are observed with a very significant drop in oxygen content - up to 15-17% (at normal - almost 21%). It should be emphasized that in in this case we're talking about about reduced oxygen content at normal atmospheric pressure.

When the air temperature increases to 35-40°C and high humidity, the partial pressure of oxygen decreases, which can have a negative effect on patients with hypoxia.

In healthy people, oxygen starvation due to a decrease in the partial pressure of oxygen can be observed when flying (altitude sickness) and when climbing mountains (mountain sickness, which begins at an altitude of about 3 km).

Altitudes of 7-8 km correspond to 8.5-7.5% oxygen in the air at sea level and for untrained people are considered incompatible with life without the use of oxygen devices.

A dosed increase in the partial pressure of oxygen in the air in pressure chambers is used in surgery, therapy and emergency care.

Oxygen in its pure form has a toxic effect. Thus, in experiments on animals it was shown that when breathing pure oxygen, animals exhibit atelectasis in the lungs after 1-2 hours, impaired capillary permeability in the lungs after 3-6 hours, and pulmonary edema after 24 hours.

Hyperoxia develops even faster in an oxygen environment with high pressure - both damage to the lung tissue and damage to the central nervous system is observed.

Carbon dioxide or carbon dioxide, in nature exists in free and bound states. Up to 70% of carbon dioxide is dissolved in the water of the seas and oceans; the composition of some mineral compounds (limestones and dolomites) includes about 22% of the total amount of carbon dioxide. The rest comes from flora and fauna. In nature, continuous processes of release and absorption of carbon dioxide occur. It is released into the atmosphere as a result of human and animal respiration, as well as combustion, rotting, and fermentation. In addition, carbon dioxide is formed during the industrial roasting of limestones and dolomites, and it can be released with volcanic gases. Along with the processes of formation in nature, there are processes of assimilation of carbon dioxide - active absorption by plants during the process of photosynthesis. Carbon dioxide is washed out of the air by precipitation.

An important role in maintaining a constant concentration of carbon dioxide in the atmospheric air is played by its release from the surface of the seas and oceans. Carbon dioxide dissolved in the water of the seas and oceans is in dynamic equilibrium with carbon dioxide in the air and, when the partial pressure in the air increases, dissolves in water, and when the partial pressure decreases, it is released into the atmosphere. The processes of formation and assimilation are interconnected, due to this the content of carbon dioxide in the atmospheric air is relatively constant and amounts to 0.03-0.04%. Recently, the concentration of carbon dioxide in the air of industrial cities has been increasing as a result of intense air pollution by fuel combustion products. The carbon dioxide content in urban air can be higher than in a clean atmosphere, up to 0.05% or more. The role of carbon dioxide in creating the “greenhouse effect”, leading to an increase in the temperature of the surface layer of air, is known.

Carbon dioxide is a physiological stimulant of the respiratory center. Its partial pressure in the blood is ensured by the regulation of acid-base balance. In the body, it is in a bound state in the form of sodium carbonate salts in plasma and red blood cells. When large concentrations of carbon dioxide are inhaled, redox processes are disrupted. The more carbon dioxide in the air we breathe, the less of it the body can release. The accumulation of carbon dioxide in the blood and tissues leads to the development of tissue anoxia. When the carbon dioxide content in the inhaled air increases to 3-4%, symptoms of intoxication are observed; at 8%, severe poisoning occurs and death occurs. The carbon dioxide content is used to judge the cleanliness of air in residential and public buildings. A significant accumulation of this compound in the air of enclosed spaces indicates a sanitary problem in the room (crowding of people, poor ventilation). MPC of carbon dioxide in air medical institutions equal to 0.07%, in the air of residential and public buildings - 0.1%. The last value is accepted as a calculation value when determining the ventilation efficiency of residential and public buildings.

Nitrogen. Along with oxygen and carbon dioxide, the composition of atmospheric air includes nitrogen, which in terms of quantitative content is the most significant part of atmospheric air.

Nitrogen belongs to the inert gases; it does not support respiration and combustion. Life is impossible in a nitrogen atmosphere. Its cycle occurs in nature. Nitrogen in the air is absorbed by certain types of soil bacteria, as well as blue-green algae. Under the influence of electrical discharges, nitrogen in the air turns into oxides, which, washed out of the atmosphere by precipitation, enrich the soil with salts of nitrous and nitric acids. Under the influence of soil bacteria, nitrous acid salts are converted into nitric acid salts, which in turn are absorbed by plants and serve for protein synthesis. It has been established that 95% of atmospheric air is assimilated by living organisms and only 5% is bound as a result of physical processes in nature. Consequently, the bulk of fixed nitrogen is of biogenic origin. Along with the absorption of nitrogen, it is released into the atmosphere. Free nitrogen is formed during the combustion of wood, coal, and oil; a small amount of free nitrogen is released during the decomposition of organic compounds by denitrifying microorganisms. Thus, in nature there is a continuous nitrogen cycle, as a result of which atmospheric nitrogen is converted into organic compounds. When these compounds decompose, nitrogen is restored and released into the atmosphere, and then it is again bound by biological objects.

Nitrogen is an oxygen diluent, and therefore performs a vital function, since breathing pure oxygen leads to irreversible changes in the body. When studying the effect of various nitrogen concentrations on the body, it was noted that its increased content in the inhaled air contributes to the onset of hypoxia and asphyxia due to a decrease in the partial pressure of oxygen. When the nitrogen content increases to 93%, death occurs. Nitrogen exhibits the most pronounced adverse properties under conditions of high pressure, which is associated with its narcotic effect. The role of nitrogen in the origin of decompression sickness is also known.

Noble gases. Inert gases include argon, neon, helium, krypton, xenon, etc. Chemically, these gases are inert; they dissolve in body fluids depending on the partial pressure. The absolute amount of these gases in the blood and tissues of the body is negligible. Among the inert gases, a special place is occupied by radon, actinon and thoron - decay products of the natural radioactive elements radium, thorium, actinium.

Chemically, these gases are inert, as noted above, and their dangerous effect on the body is associated with their radioactivity. Under natural conditions, they determine the natural radioactivity of the atmosphere.

Air temperature

Atmospheric air is heated mainly from the earth's surface due to the heat it receives from the Sun. About 47% solar energy, reaching the ground, is absorbed by the earth's surface and converted into heat. Approximately 34% of the sun's energy is reflected back into space from cloud tops and the Earth's surface, and only a fifth (19%) of the sun's energy directly heats the atmosphere. In this regard, the maximum air temperature occurs between 13 and 14 hours, when the earth's surface is heated to the greatest extent. The heated ground layers of air rise upward, gradually cooling. Therefore, with an increase in altitude above sea level, the air temperature decreases by an average of 0.6 ° C for every 100 meters of rise.

Heating of the atmosphere occurs unevenly and depends, first of all, on geographic latitude: the greater the distance from the equator to the pole, the greater the angle of inclination of the sun's rays to the plane of the earth's surface, the less energy is supplied per unit area and the less it heats it.

The difference in air temperatures depending on the latitude of the area can be very significant and amount to more than 100°C. Thus, the highest air temperatures (up to +60°C) were recorded in equatorial Africa, the minimum (up to –90°C) – in Antarctica.

Daily fluctuations in air temperature are also very significant in a number of equatorial countries, constantly decreasing towards the poles.

Daily and annual fluctuations in air temperature are influenced by a number of natural factors: the intensity of solar radiation, the nature and topography of the area, altitude above sea level, proximity of seas, the nature of sea currents, vegetation cover, etc.

The influence of unfavorable air temperature on the body is most pronounced in conditions where people stay or work outdoors, as well as in some production areas where very high or very low temperatures air. This applies to agricultural workers, construction workers, oil workers, fishermen, etc., as well as those working in hot shops, in ultra-deep mines (1-2 km), specialists servicing refrigeration units, etc.

In residential and public premises there are opportunities to ensure the most favorable air temperature (through heating, ventilation, use of air conditioners, etc.).

Atmosphere pressure

On a surface globe fluctuations in atmospheric pressure are associated with weather conditions and during the day, as a rule, do not exceed 4-5 mm Hg.

However, there are special living conditions and labor activity humans, in which there are significant deviations from normal atmospheric pressure that can have a pathological effect.

The composition of the air on earth is one of the reasons for our life. Without air, a person will live only three minutes, and after 10 clinical death will occur.

As long as we breathe, we live. On no other planet in the solar system is there such a close connection between chemistry and biology. Our world is unique.

Depending on the territory, the volume of the main component of the vital gas ranges from 16 to 20 percent - this is oxygen, the formula of which is O 2. Its variation is felt in space as “freshness” after a thunderstorm - this is ozone O 3.

From this article you will learn all the secrets of the earth's air envelope. What will happen to the world without one component? What harm can it cause? How will a slight deterioration of the atmosphere affect life?

What is air

The ancient Greeks used two words to define air: calamus, which meant the lower layers of the atmosphere (Dim), and aether meaning the bright upper layers of the atmosphere (the space beyond the clouds).

In alchemy, the symbol for air is a triangle divided in two by a horizontal line.

In the modern world, this definition would suit him - gas mixture, surrounding the planet, which protects against the penetration of solar radiation and large doses of ultraviolet radiation.

Over a multimillion-year period of development, the planet transformed gaseous substances and created a unique protective shield, which is almost impossible to see. Their mass fraction is disproportionately small for space.

Nothing else has an impact on the formation of the world. If we remember that part of the air masses is oxygen, then what will happen on earth without it? Buildings and structures will collapse.

Metal bridges and other structures that fascinate millions of tourists will turn into a single lump due to the small number of oxygen molecules (in this situation, close to zero). The life of all living organisms on the planet will worsen, and some will lead to death.

The seas and oceans, evaporating in the form of hydrogen, will disappear. And when the planet becomes like the Moon, a radiation fire will reign, burning out the remains of the flora, since without oxygen the temperature will increase very much, but without an atmosphere there will be no protection from the sun.

What is air made of?

Almost the entire earth's atmosphere consists of only five gases: nitrogen, oxygen, water vapor, argon and carbon dioxide.

Other mixtures are also present in it, but for the sake of purity of presentation, the chemical composition of water vapor will not be considered. It is worth mentioning that it occupies no more than five percent of the air mass.

Air composition in percentage

Ideally, the air collected in a jar consists of:

• 78 percent from nitrogen;
• 16 - 20 percent oxygen;
• 1 percent argon;
• three hundredths of a percent carbon dioxide;
• one thousandth of one percent neon;
• 0.0002 percent methane.

Smaller components are:

• helium - 0.000524%;
• krypton - 0.000114%;
• hydrogen - H2 0.00005%;
• xenon - 0.0000087%;
• ozone O 3 - 0.000007%;
• nitrogen dioxide - 0.000002%;
• iodine - 0.000001%;
• carbon monoxide;
• ammonia.

Composition of inhaled and exhaled air

Breathing takes precedence over other human needs. From school course Everyone knows that a person inhales oxygen and exhales carbon dioxide. Although in life there are other substances in the air besides pure O2.

Inhale - exhale. This cycle repeats about 22,000 times a day, consuming oxygen to maintain vitality. human body. The problem is that delicate lung tissue is attacked by air pollution, cleaning solutions, fibers, fumes and dust.

The first half of the article talked about reducing oxygen, but what will happen with an increase. Doubling the concentration of the main gas would lead to a reduction in fuel consumption in cars.

By breathing in more oxygen, a person would become much more psychologically positive. However, a favorable climate would allow some insects to increase in size. There are a number of theories predicting this. It seems that no one would want to encounter a spider the size of a dog, and one can only fantasize about the growth of large representatives.

By inhaling fewer heavy metals, humanity could overcome a number of complex diseases, but such a project would require a lot of effort. There is a whole program aimed at creating a practical paradise on earth: in every home, room, city or country. Its goal is to make the atmosphere cleaner, to save people from dangerous work in mines and metallurgy. A place where jobs would be occupied by masters of their craft.

It is important that you can breathe clean air, untouched by industry, but this requires political, or better yet, global will. And while people are busy looking for money and cheap (dirty) technologies, all that remains is to inhale city smog. How long this will last is unknown.

The map will allow you to clearly evaluate the atmospheric air of the capital of our homeland, which is inhaled by more than a dozen people.

Hygienic value of atmospheric air

Officially, air pollution can be defined as the content of harmful substances in the air, either particles or microscopic biological molecules that pose a danger to the health of living organisms: humans, animals or plants.

The level of air pollution in a particular location depends primarily on the source or sources of the pollution. This includes:

• car exhaust gases;
• coal power plants;
• industrial plants and other sources of pollution.

All of the above spews various types of hazardous substances and toxins into the air, exceeding the norm by tens and sometimes hundreds of times. In combination with natural sources - volcanoes, geysers, etc. - a deadly cocktail of toxic air masses is created, which is usually called “smog”.

The evidence of each person's guilt is clear. Our personal choices and industry can have a detrimental effect on much-needed gas. Over the century of technological breakthrough, nature has suffered, which means revenge is inevitable.

By increasing emissions, humanity is approaching an abyss from which there is no return and cannot be. Before it's too late, at least something should be fixed. It has been proven that alternative industrial technologies can help clean the air in Moscow, St. Petersburg, Tokyo, Berlin and any other major city.

Here are some solutions:

1. Replace gasoline with electricity in cars, and the sky over the city will become a little more beautiful.
2. Remove coal plants from cities, let them go down in the history of the country, start using the energy of the sun, water, and wind. Then, after the rain, soot will not fly out of the chimney of the next plant, but only the smell of “freshness.”
3. Plant a tree in the park. If thousands do this, then asthmatics and depressed people will stop visiting hospitals in search of a unique recipe from a psychologist.

The atmosphere is the gaseous shell of our planet, which rotates along with the Earth. The gas in the atmosphere is called air. The atmosphere is in contact with the hydrosphere and partially covers the lithosphere. But the upper limits are difficult to determine. It is conventionally accepted that the atmosphere extends upward for approximately three thousand kilometers. There it smoothly flows into airless space.

Chemical composition of the Earth's atmosphere

The formation of the chemical composition of the atmosphere began about four billion years ago. Initially, the atmosphere consisted only of light gases - helium and hydrogen. According to scientists, the initial prerequisites for the creation of a gas shell around the Earth were volcanic eruptions, which, along with lava, emitted huge amounts of gases. Subsequently, gas exchange began with water spaces, with living organisms, and with the products of their activities. The composition of the air gradually changed and modern form recorded several million years ago.

The main components of the atmosphere are nitrogen (about 79%) and oxygen (20%). The remaining percentage (1%) comes from the following gases: argon, neon, helium, methane, carbon dioxide, hydrogen, krypton, xenon, ozone, ammonia, sulfur and nitrogen dioxides, nitrous oxide and carbon monoxide, which are included in this one percent.

In addition, the air contains water vapor and particulate matter (pollen, dust, salt crystals, aerosol impurities).

Recently, scientists have noted not a qualitative, but a quantitative change in some air ingredients. And the reason for this is man and his activities. In the last 100 years alone, carbon dioxide levels have increased significantly! This is fraught with many problems, the most global of which is climate change.

Formation of weather and climate

The atmosphere plays a critical role in shaping the climate and weather on Earth. A lot depends on the amount of sunlight, the nature of the underlying surface and atmospheric circulation.

Let's look at the factors in order.

1. The atmosphere transmits the heat of the sun's rays and absorbs harmful radiation. The ancient Greeks knew that the rays of the Sun fall on different parts of the Earth at different angles. The word “climate” itself translated from ancient Greek means “slope”. So, at the equator, the sun's rays fall almost vertically, which is why it is very hot here. The closer to the poles, the greater the angle of inclination. And the temperature drops.

2. Due to the uneven heating of the Earth, air currents are formed in the atmosphere. They are classified according to their sizes. The smallest (tens and hundreds of meters) are local winds. This is followed by monsoons and trade winds, cyclones and anticyclones, and planetary frontal zones.

All these air masses are constantly moving. Some of them are quite static. For example, trade winds that blow from the subtropics towards the equator. The movement of others depends largely on atmospheric pressure.

3. Atmospheric pressure is another factor influencing climate formation. This is the air pressure on the surface of the earth. As is known, air masses move from an area with high atmospheric pressure towards an area where this pressure is lower.

A total of 7 zones are allocated. The equator is a low pressure zone. Further, on both sides of the equator up to the thirties latitudes there is an area of ​​high pressure. From 30° to 60° - low pressure again. And from 60° to the poles is a high pressure zone. Air masses circulate between these zones. Those that come from the sea to land bring rain and bad weather, and those that blow from the continents bring clear and dry weather. In places where air currents collide, atmospheric front zones are formed, which are characterized by precipitation and inclement, windy weather.

Scientists have proven that even a person’s well-being depends on atmospheric pressure. According to international standards, normal atmospheric pressure is 760 mm Hg. column at a temperature of 0°C. This indicator is calculated for those areas of land that are almost level with sea level. With altitude the pressure decreases. Therefore, for example, for St. Petersburg 760 mm Hg. - this is the norm. But for Moscow, which is located higher, normal pressure is 748 mm Hg.

The pressure changes not only vertically, but also horizontally. This is especially felt during the passage of cyclones.

The structure of the atmosphere

The atmosphere is reminiscent of a layer cake. And each layer has its own characteristics.

. Troposphere- the layer closest to the Earth. The "thickness" of this layer changes with distance from the equator. Above the equator, the layer extends upward by 16-18 km, in temperate zones by 10-12 km, at the poles by 8-10 km.

It is here that 80% of the total air mass and 90% of water vapor are contained. Clouds form here, cyclones and anticyclones arise. The air temperature depends on the altitude of the area. On average, it decreases by 0.65° C for every 100 meters.

. Tropopause- transition layer of the atmosphere. Its height ranges from several hundred meters to 1-2 km. The air temperature in summer is higher than in winter. For example, above the poles in winter it is -65° C. And above the equator it is -70° C at any time of the year.

. Stratosphere- this is a layer whose upper boundary lies at an altitude of 50-55 kilometers. Turbulence here is low, the content of water vapor in the air is negligible. But there is a lot of ozone. Its maximum concentration is at an altitude of 20-25 km. In the stratosphere, the air temperature begins to rise and reaches +0.8° C. This is due to the fact that the ozone layer interacts with ultraviolet radiation.

. Stratopause- a low intermediate layer between the stratosphere and the mesosphere that follows it.

. Mesosphere- the upper boundary of this layer is 80-85 kilometers. Complex photochemical processes involving free radicals occur here. They are the ones who provide that gentle blue glow of our planet, which is seen from space.

Most comets and meteorites burn up in the mesosphere.

. Mesopause- the next intermediate layer, the air temperature in which is at least -90°.

. Thermosphere- the lower boundary begins at an altitude of 80 - 90 km, and the upper boundary of the layer runs approximately at 800 km. The air temperature is rising. It can vary from +500° C to +1000° C. During the day, temperature fluctuations amount to hundreds of degrees! But the air here is so rarefied that understanding the term “temperature” as we imagine it is not appropriate here.

. Ionosphere- combines the mesosphere, mesopause and thermosphere. The air here consists mainly of oxygen and nitrogen molecules, as well as quasi-neutral plasma. Sun rays When entering the ionosphere, air molecules are strongly ionized. In the lower layer (up to 90 km) the degree of ionization is low. The higher, the greater the ionization. So, at an altitude of 100-110 km, electrons are concentrated. This helps to reflect short and medium radio waves.

The most important layer of the ionosphere is the upper one, which is located at an altitude of 150-400 km. Its peculiarity is that it reflects radio waves, and this facilitates the transmission of radio signals over considerable distances.

It is in the ionosphere that such a phenomenon as the aurora occurs.

. Exosphere- consists of oxygen, helium and hydrogen atoms. The gas in this layer is very rarefied and hydrogen atoms often escape into outer space. Therefore, this layer is called the “dispersion zone”.

The first scientist to suggest that our atmosphere has weight was the Italian E. Torricelli. Ostap Bender, for example, in his novel “The Golden Calf” lamented that every person is pressed by a column of air weighing 14 kg! But the great schemer was a little mistaken. An adult experiences pressure of 13-15 tons! But we do not feel this heaviness, because atmospheric pressure is balanced by the internal pressure of a person. The weight of our atmosphere is 5,300,000,000,000,000 tons. The figure is colossal, although it is only a millionth of the weight of our planet.