We live at a time when chemistry as a science has become omnipotent and has penetrated all spheres of human life. Therefore, it could not but arouse the deepest interest among ordinary people who have nothing to do with science.

We will present, understandable to everyone and everyone. One of the topical and useful questions concerns methyl alcohol.

This substance is almost impossible to distinguish from ethyl alcohol, but the impact of the former is very harmful to human health and its use can be fatal.

A very small dose of methanol can deprive a person of sight, and the use of alcohol from 30 ml leads to death.

Now it becomes clear why people are poisoned if they consume low-quality alcohol. And what is most striking is the antidote and this is ethyl alcohol.

Let's start with a historical background. We used to think that Mendeleev had a dream about the table of chemical elements, but one day he was asked this question, to which he answered clearly: “I have been thinking about it for maybe twenty years, and you think: I was sitting and suddenly… it’s ready.”

What temperature do you think water freezes at? At 0 ° C? But no. Water can turn into ice even at + 20 ° C if it contains an admixture of methane. That is, water forms a gas hydrate with methane. Water molecules are repulsed under the pressure of methane molecules. As a result, the internal water pressure decreases and the freezing point rises.

As a rule, they are obtained most often by chance. Charles Goodyear from America, through his carelessness, created a recipe for durable rubber. It does not crack at sub-zero temperatures and does not soften in extreme heat. His mistake was that he left a heated mixture of sulfur and rubber on the stove, now this process is called vulcanization.

Children's construction set "Lego" is made of plastic containing barium sulfate.

This salt is absolutely harmless to the body and does not dissolve in water. Moreover, it is well defined by X-rays, so a part swallowed by a baby can be easily found by taking a picture.

Do not miss! Top 5 fun facts: the high jaguar

There are interesting facts about chemistry concerning the plant kingdom. As you know, plants are protected from strong exposure to ultraviolet rays and heavy rainfall, but this is not their only natural feature. They are able to protect themselves from animals and insects, with the help of specific smells and enzymes that they emit at the sight of danger. In this way, plants can even kill the animal that eats them.

Everything can hardly be read in a small article, so we will briefly review the most and its elements.

• It is difficult to imagine that the human brain carries out 100,000 chemical reactions per second;
• Residents of the United States add a chemical element with a pronounced smell of rotten meat to the gas pipeline. This is necessary in order to quickly detect a leak, since vultures flock to this smell;
• About 90% of all atoms of the Universe are occupied by Hydrogen;
• Gold is not such a rare metal as we think, there is enough of this metal in the earth's crust to cover the entire surface of the planet;
• To detect bone cancer by means of X-rays, Technetium (Tc) is used;
• Triiodine nitride NI3 is a very dangerous explosive. Its temperature can rise even if a fly lands on it, resulting in an explosion.
• A lot of elements and substances of chemistry were discovered by accident and antibiotics are no exception. A test tube containing staphylococcus bacteria was accidentally left unattended by Alexander Fleming. This led to the proliferation of molds, which began to destroy bacteria. After that, Fleming received penicillin.

Do not leave science without attention, because we contain the entire periodic table, to learn interesting facts about chemistry, it means to learn something new about yourself.

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Even if you listened carefully to everything in the classroom at school and in pairs at the university, you do not know all the interesting facts about chemical elements. In this article, we will talk about interesting moments in history associated with chemical elements, as well as about their unusual properties.

1. Hydrogen

The earth's crust contains very little hydrogen - about 0.15 percent, while the same element makes up about 50% of the mass of the Sun. Something else interesting - in liquid form, hydrogen is the densest substance, and in gaseous form, on the contrary, it is the least dense.

2. Sodium

Sodium (better known as salt) originally had a different name. Until the 18th century, people called this element sodium. For this reason, sodium salts had such a strange name as hydrochloric soda, or sulphate soda. Here, in Russia, this name stuck thanks to Hermann Hess.

3. Metals

Few people know, but iron can go into a gaseous state, for this it needs to be heated up to 50,000 degrees Celsius.

4. Gold

One of the most precious metals that everyone knows - gold is found in places you never knew existed. So, in a ton of ordinary water from the ocean, it is about 7 mg. In total, the ocean contains more than 10 billion tons of this metal.

5. Platinum

At first, platinum, in view of its similarity to silver, was given a similar name - "silver". It was much cheaper than silver. Later, when they figured out where this metal could be used, everything changed dramatically. Platinum is now ten times more expensive than silver.

6. Silver

Speaking of silver, its bactericidal properties were discovered by accident. The Macedonian army underwent an epidemic, but it affected only the ordinary military, the commanders were healthy. It turned out that everything is connected with dishes. For the commanders, it was silver, for the military, it was made of tin.

7. Metals in liquid state

There are several metals that are liquid at "room" temperature: mercury, cesium, francium, and gallium.

8. Metals and planets

Previously, people knew only 7 metals and the same number of planets, so they divided them "in pairs." The moon meant silver, Mars - iron, Mercury was assigned to Mercury, the Sun, of course, gold. Jupiter became tin, Venus became copper, and Saturn became lead.

A snake made of sand. An interesting chemical experiment at home:

For many, weekdays are almost monotonous: home, work, home ... And often it drives people into depression, because there is not enough variety, events, adventures, something interesting! But in fact, millions of events and various interesting phenomena occur around us every day, which we do not pay attention to, not only because we are inattentive, but because the human eye simply does not see it.

For example, various chemical processes are constantly going on around us. It is an illusion that chemistry is something complex and incomprehensible. In fact, chemistry is a part of our life, without which human life would not only be much more boring, but generally impossible.

Amazing Chemistry Facts:

1. A soap bubble is the thinnest matter that the human eye can see. The soap bubble bursts in 0.001 seconds. At the same time, if you inflate a bubble at -15 C o, then it will freeze when it comes into contact with the surface, and at -25 C o - it freezes in the air and breaks on impact.

2. The waters of the ocean contain gold. There are 7 milligrams of gold per ton of ocean water.

3. During the flight, airplanes use up to 75 tons of oxygen, this amount of oxygen produces 30,000 hectares of forest.

4. Iron can be converted into gas at a temperature of 1539 C 0.

5. Every living organism on our planet contains protein, but in different proportions. The human brain is also a protein.

6. The lethal dose of methyl alcohol is 30 ml, while the antidote is ethyl alcohol.

7. Metal does not smell. Everyone is familiar with the smell of untreated (not painted) metal, for example, metal money, railings, old swings, fittings or just a piece of metal smell like that. But this smell is not emitted by the metal itself, it is the result of contact of the metal with an organic substance, for example, with our palm or finger, which produces sweat.

8. Tomatoes are very smart plants, they can shout "SOS!" The moment an insect - such as a caterpillar - begins to gnaw a tomato leaf, it releases a chemical with a specific odor that attracts birds.

9. Charles Goodyear is a scientist who accidentally invented rubber that does not melt in heat and does not break in cold weather. He forgot to remove the mixture of sulfur and rubber from the included stove, so a process for making rubber was invented, which was called vulcanization.

10. In the human brain every minute there are about 100 thousand chemical reactions.

Chemistry constantly surrounds us. It is found not only around us, but also inside our body, and even our thought process is, in essence, chemistry. So chemistry helps us not only to learn a lot of interesting and surprising things, but also benefits us in every sense.

By the end of the 19th century, organic chemistry was formed as a science. Interesting facts will help you better understand the world around you and find out how new scientific discoveries were made.

"Live" dish

The first interesting fact about chemistry is about fancy food. One of the famous dishes of Japanese cuisine is "Odori Donu" - "dancing squid". Many are shocked by the sight of a squid wiggling its tentacles in a plate. But do not worry, he does not suffer and has not felt anything for a long time. Freshly fresh squid is placed in a bowl of rice and poured with soy sauce before serving. The squid's tentacles begin to contract. This is due to the special structure of the nerve fibers, which for some time after the death of the animal react with sodium ions contained in the sauce, causing the muscles to contract.

Accidental discovery

Interesting facts about chemistry often relate to discoveries made by accident. So, in 1903, Edouard Benedictus, a famous French chemist, invented unbreakable glass. The scientist accidentally dropped a flask that was filled with nitrocellulose. He noticed that the flask was broken, but the glass did not shatter into pieces. After conducting the necessary research, the chemist found that damage-resistant glass could be created in this way. This is how the first safety glass for cars appeared, which significantly reduced the number of injuries in car accidents.

Live sensor

Interesting facts about chemistry tell about the use of sensitivity of animals for the benefit of humans. Until 1986, miners took canaries underground with them. The fact is that these birds are extremely sensitive to firedamp gases, especially methane and carbon monoxide. Even with a small concentration of these substances in the air, the bird can die. The miners listened to the bird's song and monitored its well-being. If the canary is worried or begins to faint, this is a signal that the mine needs to be abandoned.

The bird did not necessarily die from poisoning; it quickly became better in the fresh air. Even special sealed cages were used, which were closed when signs of poisoning. Even today, no device has been invented that senses ore gases as subtly as a canary.

Rubber

Fun fact about chemistry: Another accidental invention is rubber. Charles Goodyear, an American scientist, discovered a recipe for making rubber that does not melt in the heat and does not break in the cold. He accidentally reheated a mixture of sulfur and rubber, leaving it on the stove. The process of making rubber was called vulcanization.

Penicillin

Another interesting fact about chemistry: penicillin was invented by accident. forgot about the tube with staphylococcus bacteria for a few days. And when he remembered about her, he found that the colony was dying. It turned out to be mold, which began to destroy bacteria. It was from the scientist who received the world's first antibiotic.

Poltergeist

Interesting facts about chemistry can disprove mystical stories. You can often hear about old haunted houses. And it's all about an outdated and poorly working heating system. Poisoning leaks cause headaches and auditory and visual hallucinations in the home.

Gray cardinals among plants

Chemistry can explain the behavior of animals and plants. In the course of evolution, many plants have developed defense mechanisms against herbivores. Most often, they secrete poison from plants, but scientists have discovered a more subtle method of protection. Some plants secrete substances that attract ... predators! Predators regulate the number of herbivores and scare them away from the place where "smart" plants grow. Even plants that are familiar to us, such as tomatoes and cucumbers, have such a mechanism. For example, a caterpillar undermined a cucumber leaf, and the scent of the juice released attracted birds.

Protein Protectors

Interesting facts: chemistry and medicine are closely related. During experiments on mice, virologists discovered interferon. This protein is produced in all vertebrates. A special protein, interferon, is released from a cell infected with a virus. It has no antiviral effect, but it contacts healthy cells and makes them immune to the virus.

Smell of metal

We usually think that coins, public transport handrails, railings, etc., smell like metal. But this smell is not emitted by the metal, but by compounds that are formed as a result of contact with the metal surface of organic substances, for example, human sweat. In order for a person to feel the characteristic smell, very few reagents are needed.

Construction material

Chemistry studies proteins relatively recently. They arose over 4 billion years ago in an incomprehensible way. Proteins are a building material for all living organisms; other forms of life are unknown to science. Proteins make up half of the dry mass in most living organisms.

In 1767, he became interested in the nature of the bubbles that emerge from beer during fermentation. He collected the gas in a bowl of water, which he tasted. The water was pleasant and refreshing. Thus, the scientist discovered carbon dioxide, which is used today to produce soda water. Five years later, he described a more efficient method for producing this gas.

Sugar substitute

This interesting fact about chemistry suggests that many scientific discoveries were made almost by accident. A curious incident led to the discovery of the properties of sucralose, a modern sugar substitute. Leslie Hugh, a professor from London who studies the properties of the new substance trichlorosucrose, instructed his assistant Shashikant Pkhadnis to test it (test in English). A student with poor English skills understood the word as "taste", which means taste, and immediately followed the instructions. Sucralose turned out to be very sweet.

Flavoring

Skatole is an organic compound formed in the intestines of animals and humans. It is this substance that causes the characteristic odor of feces. But if in high concentrations skatole has the smell of feces, then in small quantities this substance has a pleasant smell, reminiscent of cream or jasmine. Therefore, skatole is used to flavor perfumery, food and tobacco products.

Cat and iodine

An interesting fact about chemistry - the most ordinary cat was directly involved in the discovery of iodine. The pharmacist and chemist Bernard Courtois usually dined in the laboratory, and he was often joined by a cat who liked to sit on the owner's shoulder. After the next meal, the cat jumped to the floor, while knocking over containers with sulfuric acid and a suspension of algae ash in ethanol, which stood at the work table. The liquids mixed, and purple vapor began to rise into the air, settling on objects in small black-violet crystals. So a new chemical element was discovered.

Interesting facts in chemistry and not only ...

Accidental discoveries

Find

In 1916, a forgotten steel cylinder with compressed carbon monoxide CO was discovered at the Baden aniline-soda factory in Germany. When the balloon was opened, about 500 ml of a yellow oily liquid with a characteristic odor and easily burned in air turned out to be at the bottom. The liquid in the cylinder was iron pentacarbonyl, which gradually formed under increased pressure as a result of the reaction

Fe + 5CO =.

The find marked the beginning of an industrial method for the production of metal carbonyls - complex compounds with amazing properties.

Argon

In 1894, the English physicist Lord Rayleigh was engaged in determining the density of gases that make up the atmospheric air. When Rayleigh began to measure the density of nitrogen samples obtained from air and from nitrogen compounds, it turned out that nitrogen released from the air is heavier than nitrogen obtained from ammonia.

Rayleigh was perplexed and looked for the source of the discrepancy. More than once he said with bitterness that he was "falling asleep over the nitrogen problem." Nevertheless, he and the English chemist Ramsay succeeded in proving that atmospheric nitrogen contains an admixture of another gas - argon Ar. This is how the first gas from the group of noble (inert) gases was discovered for the first time, which had no place in the Periodic Table.

Clathrates

Once in one of the regions of the United States, a natural gas pipeline exploded. This happened in the spring at an air temperature of 15 ° C. In the place of the pipeline rupture, inside, they found a white substance, similar to snow, with the smell of transported gas. It turned out that the rupture was caused by the blockage of the pipeline by a new natural gas compound of the composition C n H 2 n +2 (H 2 O) x, now called an inclusion compound, or clathrate. The gas was not thoroughly dried, and the water entered into intermolecular interaction with hydrocarbon molecules, forming a solid product - a clathrate. From this history, the development of the chemistry of clathrates began, which is a crystalline framework made of water molecules or another solvent, in the cavities of which hydrocarbon molecules are included.

Phosphorus

In 1669, the soldier-alchemist Hennig Brand, in search of the "philosopher's stone", evaporated the soldier's urine. He added charcoal to the dry residue and the mixture began to ignite. With surprise and fear, he saw a greenish-bluish glow emerge in his vessel. "My fire" - so named Brand the cold glow of the vapors of the white phosphorus he discovered. Until the end of his life, Brand did not know that he had discovered a new chemical element, and there were no ideas about chemical elements at that time.

Black powder

According to one of the legends, a native of Freiburg, Konstantin Anklitsen, aka the monk Berthold Schwartz, in 1313, in search of the "philosopher's stone", mixed saltpeter (potassium nitrate KNO 3), sulfur and coal in a mortar. It was already dusk and, in order to light a candle, he struck a spark from the flint. By chance, a spark fell into the mortar. There was a strong flash producing thick white smoke. This is how black powder was discovered. Berthold Schwartz was not limited to this observation. He placed the mixture in a cast-iron vessel, filled the hole with a wooden stopper, and placed a stone on top. Then he began to heat the vessel. The mixture erupted, the resulting gas knocking out the cork and hurling a stone that smashed through the door of the room. So the folklore German alchemist, in addition to gunpowder, accidentally "invented" the first "cannon".

Chlorine

The Swedish chemist Scheele once studied the effect of various acids on the pyrolusite mineral (manganese dioxide MnO 2). In the past few days, he began to heat the mineral with hydrochloric acid HCl and felt the smell characteristic of "aqua regia":

MnO 2 + 4HCl = Cl 2 + MnCl 2 + 2H 2 O.

Scheele collected the yellow-green gas that caused this smell, investigated its properties and called it "dephlogisticated hydrochloric acid, otherwise" hydrochloric acid oxide. Later it turned out that Scheele had discovered a new chemical element, chlorine Cl.

Saccharin

In 1872, a young Russian émigré Fahlberg worked in the laboratory of Professor Air Remsen (1846-1927) in Baltimore (USA). It so happened that after finishing the synthesis of some derivatives of luolsulfamide C 6 H 4 (SO 2) NH 2 (CH 3), Fahlberg went to the dining room, forgetting to wash his hands. During lunch, he felt a sweet taste in his mouth. This interested him ... He hurried to the laboratory and began to check all the reagents that he used in the synthesis. Among the waste in the waste bowl, Fahlberg discovered an intermediate synthesis product he had discarded the day before, which was very sweet. The substance was called saccharin, its chemical name is o-sulfobenzoic acid imide C 6 H 4 (SO 2) CO (NH). Saccharin is distinguished by its unusually sweet taste. Its sweetness is 500 times that of ordinary sugar. Saccharin is used as a sugar substitute for diabetics.

Iodine and cat

Friends of Courtois, who discovered the new chemical element iodine, tell interesting details of this discovery. Courtois had a beloved cat, which during dinner usually sat on the shoulder of its owner. Courtois often dined in the laboratory. One day during lunch, the cat, frightened of something, jumped to the floor, but hit the bottles that were near the laboratory table. In one bottle, Courtois prepared for the experiment a suspension of algae ash in ethanol C 2 H 5 OH, and the other contained concentrated sulfuric acid H 2 SO 4. The bottles broke and the liquids mixed. Clouds of blue-violet steam began to rise from the floor, which settled on the surrounding objects in the form of tiny black-violet crystals with a metallic sheen and a pungent odor. It was a new chemical element, iodine. Since the ash of some algae contains sodium iodide NaI, the formation of iodine is explained by the following reaction:

2NaI + 2H 2 SO 4 = I 2 + SO 2 + Na 2 SO 4 + 2H 2 O.

Amethyst

The Russian geochemist E. Emlin once walked with his dog in the vicinity of Yekaterinburg. In the grass near the road, he noticed a nondescript-looking stone. The dog began to dig the ground near the stone, and Emlin began to help her with a stick. Together, they pushed the stone out of the ground. Under the stone was a whole scattering of crystals of amethyst gemstone. The prospecting detachment of geologists who arrived at this place on the very first day mined hundreds of kilograms of the purple mineral.

Dynamite

Once, bottles of nitroglycerin, a strong explosive, were transported in crates filled with porous rock called infusorite earth, or diatomaceous earth. This was necessary to avoid damage to the bottles during transportation, which always led to an explosion of nitroglycerin. On the way, one of the bottles nevertheless broke, but the explosion did not occur. Kieselguhr absorbed all the spilled liquid like a sponge. The owner of nitroglycerin factories, Nobel, drew attention not only to the absence of an explosion, but also to the fact that diatomaceous earth absorbed almost three times the amount of nitroglycerin compared to its own weight. After conducting experiments, Nobel found that diatomaceous earth impregnated with nitroglycerin does not explode on impact. The explosion occurs only from the explosion of the detonator. This is how the first dynamite was obtained. Orders for its production fell to the Nobel from all countries.

Triplex

In 1903, the French chemist Edouard Benedictus (1879-1930), during one of his works, inadvertently dropped an empty flask on the floor. To his surprise, the flask did not break into pieces, although the walls were covered with many cracks. The reason for the strength was the film of the collodion solution, which was previously stored in the flask. Collodion is a solution of cellulose nitrates in a mixture of ethanol C 2 H 5 OH with ethyl ether (C 2 H 5) 2 O. After evaporation of solvents, cellulose nitrates remain in the form of a transparent film.

The chance gave Benedictus the idea of ​​shatterproof glass. By gluing together under slight pressure two sheets of ordinary glass with a collodion lining, and then three sheets with a celluloid lining, the chemist obtained a three-layer safety glass "triplex". Recall that celluloid is a transparent plastic obtained from collodion, to which a plasticizer, camphor, is added.

First carbonyl

In 1889, in Mond's laboratory, attention was drawn to the bright color of the flame when burning a gas mixture consisting of hydrogen H 2 and carbon monoxide CO, when this mixture was passed through nickel tubes or a nickel valve. The study showed that the reason for the color of the flame is the presence of a volatile impurity in the gas mixture. The impurity was isolated by freezing and analyzed. It turned out to be nickel tetracarbonyl. This is how the first carbonyl of metals of the iron family was discovered.

Electrotype

In 1836, the Russian physicist and electrical engineer Boris Semenovich Jacobi (1801-1874) carried out the usual electrolysis of an aqueous solution of copper sulfate CuSO 4 and saw a thin copper coating formed on one of the copper electrodes:

[Сu (Н 2 О) 4] 2+ + 2е - = Cu ↓ + 4H 2 O.

Discussing this phenomenon, Jacobi came to the idea of ​​the possibility of making copper copies from any things. This is how the development of electroforming began. In the same year, for the first time in the world, by electrolytic build-up of copper, Jacobi made a cliche for printing paper banknotes. The method he proposed soon spread to other countries.

Unexpected explosion

Once, at a chemical warehouse, they found two forgotten bottles of diisopropyl ether - a colorless liquid (CH 3) 2 CHOSN (CH 3) 2 with a boiling point of 68 0 C. To the surprise of chemists, at the bottom of the bottles there was a crystalline mass similar to camphor. The crystals looked harmless enough. One of the chemists poured the liquid into the sink and tried to dissolve the crystalline precipitate with water, but he failed. Then the bottles that could not be washed were taken to the city dump without any precautions. And there someone threw a stone at them. A violent explosion followed, equal in power to the explosion of nitroglycerin. Subsequently, it turned out that in the air as a result of slow oxidation, polymeric peroxide compounds are formed - strong oxidants, flammable and explosive substances.

Artificial blood

Chemist William-Mansfield Clark (1884-1964) from the Medical College of Alabama (USA), deciding to drown the captured rat, plunged it headlong into the first glass of silicone oil that he saw on the laboratory table. To his surprise, the rat did not choke, but breathed liquid for almost 6 hours. It turned out that the silicone oil was oxygenated for some kind of experiment. This observation was the beginning of work on the creation of "respiratory fluid" and artificial blood. Silicone oil is a liquid organosilicon polymer capable of dissolving and retaining up to 20% oxygen. The air, as you know, contains 21% oxygen. Therefore, the silicone oil provided the rat for some time. An even larger amount of oxygen (more than 1 liter for each liter of liquid) is absorbed by perfluorodecalin C 10 F 18, which is used as artificial blood.

Also a clathrate

In 1811, the English chemist Davy passed gaseous chlorine through water cooled to 0 ° C to remove hydrogen chloride impurities. It was already known then that the solubility of HCl in water sharply increases with decreasing temperature. Davy was surprised to see yellow-green crystals in the vessel. He could not establish the nature of the crystals. Only in our century it was proved that the crystals obtained by Davy have the composition Cl 2 ∙ (7 + x) H 2 O and are non-stoichiometric inclusion compounds, or clathrates. In clathrates, water molecules form peculiar cells, closed from the sides and including chlorine molecules. Davy's accidental observation laid the foundation for the chemistry of clathrates, which have a variety of practical applications.

Ferrocene

Refineries have long noticed the formation of red crystalline deposits in iron pipelines when they passed petroleum distillation products containing cyclopentadiene C 5 H 6 through them at high temperatures. Engineers were only annoyed at the need for additional cleaning of pipelines. One of the most curious engineers analyzed red crystals and found that they represent a new chemical compound, which was given the trivial name of ferrocene, the chemical name of this substance - | bis-cyclopentadienyl iron (II). The reason for the corrosion of iron pipes at the plant also became clear. She was provoked by a reaction

C 5 H 6 + Fe = + H 2

Fluoroplastic

The first polymeric material containing fluorine, known in our country as fluoroplastic, and in the USA - Teflon, was obtained by accident. Once in the laboratory of the American chemist R. Plunkett in 1938, gas stopped flowing from a cylinder filled with tetrafluoroethylene CF 2 CF 2. Plunkett turned on the tap completely, cleaned the hole with a wire, but the gas did not come out. Then he shook the container and felt that inside it instead of gas there was some kind of solid substance. The container was opened and white powder spilled out. It was a polymer - polytetrafluoroethylene, called Teflon. A polymerization reaction has passed in the cylinder

n (CF 2 CF 2) = (-CF 2 -CF 2 -CF 2 -) n.

Teflon is resistant to the action of all known acids and their mixtures, to the action of aqueous and non-aqueous solutions of alkali metal hydroxides. It can withstand temperatures from -269 to + 200 ° C.

Urea

In 1828, the German chemist Wöhler tried to obtain crystals of ammonium cyanate HH 4 NCO. He passed ammonia through an aqueous solution of cyanic acid HNCO according to the reaction

HNCO + NH 3 = NH 4 NCO.

The resulting Wöhler solution was evaporated until colorless crystals were formed. Imagine his surprise when the analysis of the crystals showed that he had not obtained ammonium cyanate, but the well-known urea (NH 2) 2 CO, now called urea. Before Vöhler, urea was obtained only from human urine. An adult excretes about 20 g of urea in the urine every day. Wöhler, none of the chemists of that time believed that organic matter could be obtained outside a living organism. It was believed that organic matter can be formed only in a living organism under the influence of "life force". When Wöhler informed the Swedish chemist Berzelius about his synthesis, he received the following answer from him: "... The one who initiated his immortality in urine has every reason to complete his path of ascension to heaven with the help of the same object ..."

Wöhler's synthesis opened up a broad road to obtaining numerous organic substances from inorganic ones. Much later it was found that when heated or when dissolved in water, ammonium cyanate is converted into urea:

NH 4 NCO = (NH 2) 2 CO.

Zinkal

Already in our century, one of the metallurgists obtained an alloy of aluminum A1 with 22% zinc Zn, which he called zinc. To study the mechanical properties of zinc, the metallurgist made a plate from it and soon forgot about it, while engaged in the production of other alloys. During one of the experiments, in order to protect his face from the heat radiation of the burner, he fenced off with a plate of zinc that was at hand. Upon completion of the work, the metallurgist was surprised to find that the plate had elongated more than 20 times without any signs of destruction. This is how a group of superplastic alloys was discovered. The superplastic deformation temperature of zinc was found to be 250 ° C, much less than the melting point. At 250 ° C, the zincal plate begins to literally flow under the influence of gravity, without passing into a liquid state.

Studies have shown that superplastic alloys are formed by very fine grains. When heated under a very small load, the plate is elongated due to an increase in the number of grains along the direction of stretching while reducing the number of grains in the transverse direction.

Benzene

In 1814 gas lighting appeared in London. The luminescent gas was stored in pressurized iron cylinders. On summer nights, the lighting was normal, and in winter, in extreme cold, it was dim. The gas, for some reason, did not give a bright light.

The owners of the gas plant turned to chemist Faraday for help. Faraday established that in winter, part of the lamp gas collects at the bottom of the cylinders in the form of a transparent liquid of the composition C 6 H 6. He called it "carbureted hydrogen." It was benzene, now well-known to everyone. The honor of discovering benzene remained with Faraday. The name "benzene" was given to the new substance by the German chemist Liebig.

White and gray tin

The second and last expedition of the English traveler Robert Falcon Scott in 1912 to the South Pole ended tragically. In January 1912, Scott and four of his friends reached the South Pole on foot and found from an abandoned tent and a note that just four weeks earlier, the South Pole had been discovered by Amundsen's expedition. With chagrin, they set off on their way back in a very severe frost. At the intermediate base where the fuel was stored, they did not find it. The iron cans of kerosene were empty, as they had "someone opened the seams" that had previously been sealed with tin. Scott and his companions froze near the unsoldered canisters.

So, under tragic circumstances, it was discovered that at low temperatures tin passes into another polymorphic modification, called the "tin plague". The transition to the low-temperature modification is accompanied by the transformation of ordinary tin into dust. White tin, or β-Sn, with which the canisters were sealed, turned into gray dusty tin, or α-Sn. Death overtook Scott and his companions only 15 km from the place where the main part of the expedition was waiting for them, which included two Russians - Girev and Omelchenko.

Helium

In 1889, the English chemist D. Matthews treated the mineral cleveite with heated sulfuric acid H 2 SO 4 and was surprised to see the release of an unknown gas that did not burn and did not support combustion. It turned out to be helium He. Cleveite, a rare mineral in nature, is a type of uraninite mineral with the composition UO 2. It is a highly radioactive mineral that emits alpha particles, the nuclei of helium atoms. By attaching electrons, they turn into helium atoms, which in the form of small bubbles remains embedded in the crystals of the mineral. When it is treated with sulfuric acid, the reaction proceeds

UO 2 + 2H 2 SO 4 = (UO 2) SO 4 + SO 2 + 2H 2 O.

Uranium dioxide UO 2 goes into solution in the form of uranyl sulfate (UO 2) SO 4, and He is released and is released in the form of a gas together with sulfur dioxide SO 2. Especially a lot was not found in the mineral thorianite, thorium dioxide and uranium (Th, U) O 2: 1 liter of thorianite, when heated to 800 ° C, releases almost 10 liters of He.

In 1903, an oil company was prospecting for oil in the state of Kansas (USA). At a depth of about 100 m, she came across a gas reservoir, which gave a fountain of gas. To the great amazement of the oilmen, the gas did not burn. It was helium too.

Purple

The Roman encyclopedic scientist Mark Terenty Varro (116-27 BC) in his work "Human and Divine Antiquities" told a legend.

Once a resident of the Phoenician city of Tire was walking along the seashore with a dog. The dog, finding among the pebbles a small shell thrown out by the surf, crushed it with his teeth. The dog's mouth immediately turned red and blue. This is how the famous natural dye was discovered - antique purple, which was also called Tyrian purple, royal purple. This dye was used to stain the clothes of the emperors of Ancient Rome. The source of purple is predatory purple molluscs, which feed on other mollusks, first destroying their shells with acid secreted by the salivary glands. The purple was extracted from the purple glands of the purplish. In the past, the color of paints was identified with various symbols. Purple was a symbol of dignity, strength and power.

In 1909, the German chemist Paul Friedländer (1857-1923) obtained dibromindigo 2 by a complex synthesis and proved its identity with the purple of the Mediterranean crimson.

Uranium radiation

French physicist Becquerel studied the glow of certain crystals, called phosphorus, in the dark after preliminary exposure to sunlight. Becquerel had a large collection of phosphorus, and among them was uranyl potassium sulfate K 2 (UO 2) (SO 4) 2. After the discovery of X-rays, Becquerel decided to find out if his phosphorus emitted these rays, causing the blackening of a photographic plate covered with black opaque paper. He wrapped the photographic plate in such paper, and on top he put this or that phosphorus, previously exposed to the sun. One day in 1896, on cloudy days, Becquerel, unable to stand in the sun, uranyl-potassium sulfate, put it on a wrapped plate in anticipation of sunny weather. For some reason, he decided to develop this photographic plate and discovered on it the outlines of a lying crystal. It became clear that the penetrating radiation of the uranium salt U has nothing to do with the phosphorus luminescence, that it exists independently of anything.

So the natural radioactivity of uranium compounds was discovered, and then thorium Th. Becquerel's observations served as a basis for Pierre and Marie Curie to search for new, more radioactive chemical elements in uranium minerals. The polonium and radium they found turned out to be products of the radioactive decay of uranium atoms.

Litmus

Once the English chemist Boyle prepared an aqueous infusion of litmus lichen. The bottle in which he kept the infusion was needed for the hydrochloric acid HCl. Pouring out the infusion, Boyle poured acid into a bottle and was surprised to find that the acid turned red. Then he added a few drops of the infusion to an aqueous solution of sodium hydroxide NaOH and saw that the solution turned blue. This is how the first acid-base indicator called litmus was discovered. Subsequently, Boyle, and then other researchers began to use pieces of paper soaked in infusion of litmus lichen and then dried. Litmus papers turned blue in an alkaline solution and red in an acidic solution.

Bartlett's opening

Canadian student Neil Bartlett (b. 1932) decided to purify platinum hexafluoride PtF 6 from the impurity of bromides by passing gaseous fluorine F 2 over it. He believed that the liberated bromine Br 2 should turn in the presence of fluorine into a light yellow bromine trifluoride BrF 3, which, upon cooling, would become a liquid:

NaBr + 2F 2 = NaF + BrF 3.

Instead, Bartlett saw the release of a large amount of red vapor, turning into red crystals on the cold parts of the instrument. Bartlett managed to find the answer to this unusual phenomenon only two years later. Platinum hexafluoride was stored in air for a long time, and, being a very strong oxidizing agent, gradually interacted with atmospheric oxygen, forming orange crystals, dioxygenyl hexafluoroplatinate:

O 2 + PtF 6 = O 2.

The O 2 + cation is called dioxygenyl cation. When heated in a stream of fluorine, this substance sublimated in the form of a red vapor. Analysis of this random phenomenon led Bartlett to the conclusion that it is possible to synthesize compounds of noble (inert) gases. In 1961, Bartlett, already a professor of chemistry, mixing PtF 6 with xenon Xe, obtained the first compound of noble gases - xenon hexafluoroplatinate Xe.

Phosgene

In 1811, the English chemist Davy, forgetting that the vessel was already containing carbon monoxide CO, a colorless and odorless gas, admitted chlorine C1 2 into this vessel, which he wanted to save for the experiments scheduled for the next day. The closed vessel remained on the laboratory table near the window. The day was bright and sunny. The next morning, Davy saw that the chlorine in the vessel had lost its yellowish-greenish color. Opening the tap of the vessel, he smelled a peculiar smell, reminiscent of the smell of apples, hay or decaying foliage. Davy examined the contents of the vessel and established the presence of a new gaseous substance CC1 2 O, which he gave the name "phosgene", which in Greek means "born of light". The modern name CC1 2 O is carbon monoxide dichloride. A reaction proceeded in a vessel exposed to light

CO + C1 2 = CC1 2 O.

This is how a strong toxic substance of general toxic action was discovered, which was widely used in the First World War.

The ability to gradually infect the body in the smallest concentrations made phosgene a dangerous poison, whatever its content in the air.

In 1878, it was discovered that phosgene is formed from a mixture of CO and C1 2 in the dark, if this mixture contains a catalyst - activated carbon.

Under the action of water, phosgene is gradually destroyed with the formation of carbonic H 2 CO 3 and hydrochloric HCl acids:

CCl 2 О + 2Н 2 О = Н 2 СО 3 + 2HCl

Aqueous solutions of potassium hydroxides KOH and sodium NaOH destroy phosgene instantly:

CCl 2 O + 4KOH = K 2 CO 3 + 2KCl + 2H 2 O.

Phosgene is currently used in numerous organic syntheses.

Surik

This event took place over 3000 years ago. The renowned Greek painter Nikias was awaiting the arrival of the whitewash ordered by him from the island of Rhodes in the Mediterranean Sea. The paint ship arrived at the Athenian port of Piraeus, but a fire suddenly broke out there. The flames engulfed Nikiya's ship as well. When the fire was extinguished, the upset Nikias approached the remains of the ship, among which he saw charred barrels. Instead of white, he found some bright red substance under a layer of coal and ash. Nikiya's tests showed that this substance is an excellent red dye. So the fire in the port of Piraeus suggested the way of making a new paint, later called red lead. To obtain it, they began to calcine white or basic lead carbonate in air:

2 [Рb (ОН) 2 ∙ 2РbСО 3] + О 2 = 2 (Pb 2 II Pb IV) O 4 + 4CO 2 + 2Н 2 О.

Red lead (IV) -dislead (II) tetroxide.

Doebereiner's fire

The phenomenon of the catalytic action of platinum was discovered by chance. German chemist Döbereiner was involved in the chemistry of platinum. He obtained spongy, very porous platinum ("platinum mobile") by calcining ammonium hexachloroplatinate (NH 4) 2:

(NH 4) 2 = Pt + 2NH 3 + 2Cl 2 + 2HCl.

In 1823, during one of the experiments, a piece of spongy platinum Pt was found near the device for producing hydrogen H 2. A jet of hydrogen, mixed with air, hit the platinum, the hydrogen burst into flames and ignited. Döbereiner immediately appreciated the significance of his discovery. There were no matches at that time. He designed a device for igniting hydrogen, called the "Döbereiner's flint", or "incendiary machine". This device was soon sold throughout Germany.

Döbereiner received platinum from Russia from the Urals. In this he was helped by his friend I.-V. Goethe, Minister of the Duchy of Weimar during the reign of Karl-August. The duke's son was married to Maria Pavlovna, the sister of two Russian tsars - Alexander I and Nicholas I. It was Maria Pavlovna who mediated in Döbereiner's getting platinum from Russia.

Glycerin and acrolein

In 1779, the Swedish chemist Scheele discovered glycerin HOCH 2 CH (OH) CH 2 OH. To study its properties, he decided to free the substance from water impurities. Having added a dehydrating substance to glycerin, Scheele began to distill glycerin. Having entrusted this work to his assistant, he left the laboratory. When Scheele returned, the assistant was lying unconscious near the laboratory table, and there was a sharp, pungent smell in the room. Scheele felt his eyes, due to the abundance of tears, stop distinguishing anything. He quickly pulled the assistant out into the fresh air and ventilated the room. Only a few hours later did the assistant Scheele regain consciousness with difficulty. So it was established the formation of a new substance - acrolein, which in translation from Greek means "spicy oil".

The reaction of formation of acrolein is associated with the separation of two water molecules from glycerin:

C 3 H 8 O 3 = CH 2 (CH) CHO + 2H 2 O.

Acrolein has the composition CH 2 (CH) CHO and is an acrylic acid aldehyde. It is a colorless, low-boiling liquid, the vapor of which is highly irritating to the mucous membranes of the eyes and respiratory tract, and has a toxic effect. The well-known smell of burnt fats and oils, a fading sebaceous candle, depends on the formation of trace amounts of acrolein. Currently, acrolein is widely used in the preparation of polymeric materials and in the synthesis of various organic compounds.

Carbon dioxide

The English chemist Priestley discovered that in the "tainted air" (as he called carbon dioxide CO 2) animals die. And the plants? He placed a small pot of flowers under a glass jar and placed a lighted candle next to it to "spoil" the air. Soon the candle went out due to the almost complete conversion of the oxygen under the hood into carbon dioxide:

C + O 2 = CO 2.

Priestley moved the hat with a flower and an extinguished candle to the window and left it until the next day. In the morning, he was surprised to notice that the flower not only had not wilted, but another bud had opened on a branch nearby. Excitedly, Priestley lit another candle and quickly brought it under the hood and placed it next to the first candle. The candle continued to burn. Where did the "spoiled air" disappear to?

This is how the ability of plants to absorb carbon dioxide and release oxygen was discovered for the first time. At the time of Priestley, they did not yet know the composition of the air, nor did they know the composition of carbon dioxide.

Hydrogen sulfide and sulfides

The French chemist Proust studied the effect of acids on natural minerals. In some experiments, a disgustingly odorous gas, hydrogen sulfide H 2 S, was invariably emitted. One day, acting on the mineral sphalerite (zinc sulfide ZnS) with hydrochloric acid HCl:

ZnS + 2HCl = H 2 S + ZnCl 2,

Proust noticed that a blue aqueous solution of copper sulfate CuSO 4 in a glass next to him was covered with a brown film. He moved the glass with the blue solution closer to the glass from which H 2 S was released, and, not paying attention to the smell, began to stir the blue solution. Soon the blue color disappeared, and a black sediment appeared at the bottom of the glass. Analysis of the sediment showed that it is copper sulfide:

CuSO 4 + H 2 S = CuS ↓ + H 2 SO 4.

So, apparently, for the first time the formation of sulfides of some metals was discovered under the action of hydrogen sulfide on their salts.

Diamond rush

A diamond deposit in Brazil was discovered by accident. In 1726, the Portuguese miner Bernard da Fonsena-Labo at one of the gold mines saw that the workers during the rationing! games mark the score of a win or a loss with shiny transparent stones. Labo recognized them as diamonds. He had the patience to conceal his discovery. He took some of the largest stones from the workers. However, during the sale of diamonds in Europe, Labo could not hide his find. Crowds of diamond seekers poured into Brazil, and the "diamond rush" began. And here is how the diamond deposits were discovered in South Africa, which now supplies the bulk of them to the international market. In 1867, John O'Relly, a trader and hunter, stopped overnight at the farm of the Dutchman Van-Nickerk, which stood on the banks of the river. Vaal. His attention was attracted by a transparent pebble with which the children were playing. “It looks like a diamond,” O'Relly said. Van-Niekerk laughed: "You can take it for yourself, there are many such stones here!" In Cape Town, O'Relly checked with a jeweler that it was indeed a diamond and sold it for $ 3,000. O'Relly's find became widely known, and the Van-Niekerk farm was literally smashed to pieces, breaking the entire neighborhood in search of diamonds.

Boron crystals

The French chemist Saint-Clair-Deville, together with the German chemist Wöhler, set up an experiment on obtaining amorphous boron B by reacting boron oxide B 2 O 3 with metallic aluminum A1. They mixed these two powdered substances and began to heat the resulting mixture in a crucible. The reaction started at a very high temperature

B 2 O 3 + 2A1 = 2B + A1 2 O 3

When the reaction was over and the crucible cooled down, chemists poured its contents onto a porcelain tile. They saw a white powder of aluminum oxide A1 2 O 3 and a piece of metallic aluminum. There was no brown amorphous boron powder. This puzzled the chemists. Then Wöhler proposed to dissolve the remaining piece of aluminum in hydrochloric acid HCl:

2Аl (В) + 6НСl = 2АlСl 3 + 2В ↓ + 3Н 2.

After the end of the reaction, they saw black shiny boron crystals at the bottom of the vessel.

This is how one of the methods was found for obtaining a crystalline bora-chemically inert material that does not interact with acids. At one time, crystalline boron was obtained by fusing amorphous boron with aluminum, followed by the action of hydrochloric acid on the alloy. Then it turned out that the boron obtained in this way always contains an admixture of aluminum, apparently in the form of its boride AlB 12. Crystalline boron in terms of hardness ranks second among all simple substances after diamond.

Agatha

One German shepherd in 1813 found yellowish and gray stones - agates near an abandoned quarry. He decided to give them to his wife and put them for a while by the fire. Imagine his surprise when in the morning he saw that some agates turned red, while others got a reddish tint. The shepherd took one of the stones to a familiar jeweler and shared his observation with him. Soon the jeweler opened a workshop for making red agates, and later sold his recipe to other German jewelers. So a way was found to change the color of some precious stones when they are heated. Note that the price of red agate at that time was twice as much as that of yellow, and even more so of their gray varieties.

Ethylene

German alchemist, physician and inventor-dreamer Johann-Joachia Becher (1635-1682) in 1666 conducted experiments with sulfuric acid H 2 SO 4. In one of the experiments, instead of adding another portion of it to the heated concentrated sulfuric acid, absentmindedly he added ethanol C 2 H 5 OH, which was nearby in a glass. Becher saw a strong foaming of the solution with the release of an unknown gas, similar to methane CH 4. Unlike methane, the new gas burned with a smoky flame and had a faint odor. Becher found that his "air" is more chemically active than methane. This is how ethylene C 2 H 4 was discovered, formed by the reaction

C 2 H 5 OH = C 2 H 4 + H 2 O.

The new gas was called "oil gas", its combination with chlorine began to be called from 1795 "the oil of Dutch chemists". Only from the middle of the XIX century. Becher's gas was named ethylene. This name has remained in chemistry to this day.

Explosion in Oppau

In 1921 in the city of Oppau (Germany) an explosion occurred at a plant that produced fertilizers - a mixture of ammonium sulfate and nitrate - (NH 4) 2 SO 4 and NH 4 NO 3. These salts were stored in the warehouse for a long time and caked; it was decided to crush them with small explosions. This caused a detonation in the entire mass of the substance, which was previously considered safe. The explosion led to the death of 560 people and a large number of wounded and injured, not only the city of Oppau was completely destroyed, but also some houses in Mannheim - 6 km from the explosion site. Moreover, the blast wave knocked out windows in houses located 70 km from the plant.

Earlier, in 1917, a monstrous explosion occurred at a chemical plant in Halifax (Canada) due to the self-decomposition of NH 4 NO 3, which cost the lives of 3,000 people.

It turned out that ammonium nitrate is dangerous to handle and is an explosive. When heated to 260 ° C, NH 4 NO 3 decomposes into dinitrogen oxide N 2 O and water:

NH 4 NO 3 = N 2 O + 2H 2 O

Above this temperature, the reaction becomes more complicated:

8NH 4 NO 3 = 2NO 2 + 4NO + 5N 2 + 16H 2 O

and leads to a sharp increase in pressure and explosion, which can be promoted by the compressed state of the substance and the presence of an impurity of nitric acid HNO 3 in it.

Beotolle and matches

The explosive properties of potassium trioxochlorate KClO 3 Berthollet discovered by chance. He began to grind KClO 3 crystals in a mortar, in which a small amount of sulfur remained on the walls, which had not been removed by his assistant from the previous operation. Suddenly there was a violent explosion, the pestle was torn out of Berthollet's hands, his face was burned. So Berthollet was the first to carry out a reaction, which will be used much later in the first Swedish matches:

2KClO 3 + 3S = 2KCl + 3SO 2.

Potassium trioxochlorate KClO 3 has long been called berthollet's salt.

Quinine

Malaria is one of the most ancient diseases known to mankind. There is a legend about how a cure for her was found. A sick Peruvian Indian, exhausted by fever and thirst, wandered aimlessly near his village in the jungle. He saw a puddle of fairly clear water in which a fallen tree lay. The Indian began to drink the water greedily and tasted bitter. A miracle happened. The water brought him healing. The fallen tree was called by the Indians "hina-hina". Local residents, having learned about the healing, began to use the bark of this tree as a medicine against fever. Rumors reached the Spanish conquerors and reached Europe. This is how quinine C 20 H 24 N 2 O 2 was discovered - a crystalline substance extracted from the bark of the cinchona tree - cinchona. Cinchona bark during the Middle Ages was sold literally gram for gram of gold. Artificial synthesis of quinine is very difficult, it was developed only in 1944.

Miracles of Catalysis

Brother G. Davy Edward received a very fine powder of black platinum, which became known as "platinum black." Once Edward inadvertently spilled some of this powder on filter paper, with which he had just wiped off spilled ethyl alcohol C 2 H 5 OH. With surprise, he saw how the "platinum rabble" heated up and glowed until all the alcohol disappeared along with the burnt paper. This is how the reaction of catalytic oxidation of ethyl alcohol in acid was discovered:

C 2 H 5 OH + O 2 = CH 3 COOH + H 2 O

Curing

The American chemist Charles Goodyear (1800-1860) considered rubber to be a type of leather and tried to modify it. He mixed raw rubber with every substance that came to hand: salt it, pepper it, sprinkle it with sugar, river sand. One day in 1841, he dropped a piece of sulfur-treated rubber onto a heated oven. The next day, preparing the oven for the experiment, Goodyear picked up this piece and found that the rubber had become stronger. This observation of Goodyear formed the basis for the later developed rubber vulcanization process. During vulcanization, linear rubber macromolecules interact with sulfur, forming a three-dimensional network of macromolecules. As a result of vulcanization, the rubber turns into rubber. Subsequently Goodyear wrote: "I admit that my discoveries were not the result of scientific chemical research ... they were the result of perseverance and observation."

Adsorption

In 1785 Lovitz recrystallized tartaric acid and often obtained not colorless, but brown crystals due to organic impurities in them. One day, he inadvertently spilled some of the solution onto a mixture of sand and coal in a sand bath used to evaporate solutions. Lovitz tried to collect the spilled solution, filtered it from the sand and coal. When the solution cooled down, colorless transparent crystals of acid precipitated. Since sand could not be the reason, Lovitz decided to test the effect of coal. He sheltered a new acid solution, poured coal powder into it, evaporated it and then cooled it after removing the coal. The precipitated crystals were again colorless and transparent.

So Lovitz discovered the adsorptive properties of charcoal. He suggested storing drinking water on ships in wooden barrels with a layer of coal. The water hasn't rotted for months. This discovery immediately found application in the active army, in battles with the Turks in 1791 in the lower reaches of the Danube, where the water was not drinkable. Lovitz also used charcoal to purify vodka from fusel oils, acetic acid from impurities that gave it a yellow color, and in many other cases.

Mellitic acid

In order to purify the nitric acid HNO 3 from impurities, Lovitz poured a small amount of charcoal into it and began to boil this mixture. With surprise, he saw the disappearance of charcoal and the formation of some kind of white substance, soluble in water and ethanol C 2 H 5 OH, instead. He called this substance "soluble carbon". The interaction of coal with nitric acid proceeds in accordance with the reaction

12C + 6HNO 3 = C 6 (COOH) 6 + 6NO.

After 150 years, it was established that Lovitz was the first to obtain benzenehexacarboxylic acid C 6 (COOH) 6, the old name of this substance is "mellitic acid".

Zeise Salts

In 1827, the Danish organic chemist and pharmacist William Zeise (1789-1847) decided to obtain potassium tetrachloroplatinate K 2 for one of his works. To complete the precipitation of this salt, poorly soluble in ethanol, instead of an aqueous solution of H 2, he used a solution of this acid in ethanol C 2 H 5 OH. When Zeise added an aqueous solution of potassium chloride KCl to such a solution, unexpectedly, instead of a red-brown precipitate characteristic of K 2, a yellowish precipitate formed. Analysis of this precipitate showed that it contains potassium chloride KCl, platinum dichloride PtCl 2, water H 2 O and, to the surprise of all chemists, an ethylene molecule C 2 H 4: KCl ∙ PtCl 2 ∙ C 2 H 4 ∙ H 2 O This empirical formula has become the subject of heated debate. Liebig, for example, said that Zeise had carried out the analyzes incorrectly and that the formula he presented was a figment of a sick imagination. Only in 1956 it was possible to establish that the composition of the new salt was correctly established by Zeise, and now the formula of the compound is written as K ∙ H 2 O and it is called monohydrate of potassium trichloroethylene platinate.

So the first compound from an unusual group of complex compounds called "π-complexes" was obtained. In such complexes, there is no usual chemical bond of the metal inside the square brackets with any one atom of an organic particle. The reaction that Zeise carried out:

H 2 + KCl + C 2 H 5 OH = K ∙ H 2 O + 2HCl.

Currently, K is obtained by passing ethylene through an aqueous solution of potassium tetrachloroplatinate K 2:

K 2 + C 2 H 4 = K + KCl.

Bumblebee savior

Courtois, the discoverer of iodine, almost died one day. In 1813, after one of his works, he poured into an empty bottle for waste the remains of an aqueous solution of ammonia NH 3 and an alcohol solution of iodine I 2. Courtois saw the formation of a black-brown sediment in the bottle, which immediately interested him. He filtered the precipitate, washed it with ethanol C 2 H 5 OH, removed the filter with the precipitate from the funnel and left it on the laboratory bench. It was late, and Courtois decided to analyze the sediment the next day. When in the morning he opened the door to the laboratory, he saw a bumblebee flying into the room sat down on the sediment he received. Immediately there was a violent explosion that blew the laboratory table to pieces, and the room was filled with purple iodine vapor.

Courtois later said that the bumblebee saved his life. This is how a very dangerous substance was obtained and tested - triiodine nitride monoammiakate I 3 N ∙ NH 3. The synthesis reaction of this substance:

3I 2 + 5NH 3 = I 3 N ∙ NH 3 ↓ + 3NH 4.

Reaction with an explosion caused by the lightest touch or shaking of dry I 3 N ∙ NH 3:

2 (I 3 N ∙ NH 3) = 2N 2 + 3I 2 + 3H 2.

Unsuccessful experience

Fluorine F 2 was unexpectedly obtained by the French chemist Moissant. In 1886, having studied the experience of his predecessors, he subjected to electrolysis anhydrous hydrogen fluoride HF in a platinum Y-shaped tube. With surprise, Moissan noticed the release of fluorine at the anode, and hydrogen at the cathode. Inspired by success, he repeated the experiment at a meeting of the Paris Academy of Sciences, but ... did not receive fluorine. The experiment failed. After a thorough study of the reasons for the failure, Moissan found that the hydrogen fluoride he used in the first experiment contained an admixture of potassium hydrofluoride KHF 2. This impurity provided the electrical conductivity of the solution (anhydrous HF-non-electrolyte) and created the required concentration of F - ions at the anode:

2F - - 2e - = F 2.

Since then, fluorine has been obtained by the Moissan method using a solution of potassium fluoride KF in HF:

KF + HF = KHF 2.

Aspartame

Aspartame (in Russia - "sladex") - a substance recommended for use by diabetics and obese people, 100-200 times sweeter than sucrose. It does not leave behind the bitter metallic aftertaste inherent in saccharin. The sweet taste of aspartame was discovered by accident in 1965. The chemist who worked with this substance bit off the burr and tasted it sweet. Aspartame is a colorless crystal, readily soluble in water. It's a tiny protein. It is absorbed by the human body and is the source of the amino acids it needs. Aspartame does not stimulate the formation of dental caries, and its absorption does not depend on the production of insulin by the body.

Carbide

In 1862, the German chemist Wöhler tried to isolate metallic calcium from lime (calcium carbonate CaCO 3) by prolonged calcination of a mixture of lime and coal. He received a sintered mass of grayish color, in which he did not find any signs of metal. With chagrin, Wöhler threw this mass as a waste product in a landfill in the yard. During the rain, Vöhler's laboratory assistant noticed the release of some kind of gas from the ejected rocky mass. Vöhler was interested in this gas. Gas analysis showed that it is acetylene H 2 C 2, discovered by E. Davy in 1836. This is how calcium carbide CaC 2 was first discovered, interacting with water with the release of acetylene:

5C + 2CaCO 3 = 3CaC 2 + 3CO 2;

CaC 2 + 2H 2 O = H 2 C 2 + Ca (OH) 2.

From the point of view of the ignorant ...

How Berzelius made his accidental discoveries, says his laboratory assistant. Berzelius led a secluded life. Curious residents of Stockholm have repeatedly asked the laboratory assistant Berzelius how his owner works.

Well, - answered the laboratory assistant, - I first take out various things for him from the closet: powders, crystals, liquids.

He takes it all and dumps it into one large vessel.

Then he pours everything into a small vessel.

And what does he do then?

Then he pours everything into the garbage can, which I take out every morning.

In conclusion, we quote the words of the German natural scientist Hermann Helmholtz (1821-1894): “Sometimes a lucky chance can come to the rescue and reveal an unknown relationship, but the chance will hardly find application if the one who meets him has not already collected enough visual material to convince him of the correctness of the foreboding ”.

The theory of chemical evolution or how life began

The theory of chemical evolution - the modern theory of the origin of life - is based on the idea of ​​spontaneous generation. It is not based on sudden the emergence of living things on Earth, and the formation of chemical compounds and systems that make up living matter. She considers the chemistry of the ancient Earth, primarily the chemical reactions that took place in the primitive atmosphere and in the surface layer of water, where, in all likelihood, the light elements that make up the basis of living matter were concentrated, and a huge amount of solar energy was absorbed. This theory tries to answer the question: how could organic compounds spontaneously arise and form into a living system in that distant era?

The general approach to chemical evolution was first formulated by the Soviet biochemist A.I. Oparin (1894-1980). In 1924, his small book devoted to this issue was published in the USSR; in 1936 its new, supplemented edition was published (in 1938 it was translated into English). Oparin drew attention to the fact that modern conditions on the Earth's surface prevent the synthesis of a large number of organic compounds, since free oxygen, which is present in excess in the atmosphere, oxidizes carbon compounds to carbon dioxide (carbon dioxide, CO 2). In addition, he noted that in our time any organic matter "left to the mercy" on the earth is used by living organisms (a similar idea was expressed by Charles Darwin). However, Oparin argued, different conditions prevailed on the primordial Earth. It can be assumed that oxygen was absent in the earth's atmosphere at that time, but hydrogen and gases containing hydrogen such as methane (CH 4) and ammonia (NH 3) were abundant. (Such an atmosphere, rich in hydrogen and poor in oxygen, is called reducing, in contrast to the modern, oxidizing, atmosphere, rich in oxygen and poor in hydrogen.) According to Oparin, such conditions created excellent opportunities for the spontaneous synthesis of organic compounds.

Substantiating his idea of ​​the restorative nature of the primitive atmosphere of the Earth, Oparin put forward the following arguments:

1. Hydrogen is abundant in stars

2. Carbon is found in the spectra of comets and cool stars in the composition of CH and CN radicals, while oxidized carbon is rare.

3. Hydrocarbons, i.e. compounds of carbon and hydrogen are found in meteorites.

4. The atmospheres of Jupiter and Saturn are extremely rich in methane and ammonia.

As Oparin pointed out, these four points indicate that the universe as a whole is in a restorative state. Therefore, on the primitive Earth, carbon and nitrogen should have been in the same state.

5. Volcanic gases contain ammonia. This, Oparin believed, suggests that nitrogen was present in the primary atmosphere in the form of ammonia.

6. Oxygen contained in the modern atmosphere is produced by green plants in the process of photosynthesis, and, therefore, by its origin it is a biological product.

Based on these considerations, Oparin came to the conclusion that carbon on primitive Earth first appeared in the form of hydrocarbons, and nitrogen in the form of ammonia. Further, he suggested that in the course of the currently known chemical reactions on the surface of the lifeless Earth, complex organic compounds arose, which, after a rather long period of time, apparently gave rise to the first living beings. The first organisms were probably very simple systems, capable only of replication (division) due to the organic environment from which they were formed. In modern parlance, they were “heterotrophs”, that is, they depended on the environment that supplied them with organic food. At the opposite end of this scale are "autotrophs" - for example, organisms such as green plants, which themselves synthesize all the necessary organic matter from carbon dioxide, inorganic nitrogen and water. According to Oparin's theory, autotrophs appeared only after heterotrophs depleted the supply of organic compounds in the primitive ocean.

J. B.S. Haldane (1892-1964) put forward an idea, in some respects similar to Oparin's views, which was outlined in a popular essay published in 1929. He suggested that organic matter synthesized by natural chemical processes that took place on prebiological Earth, accumulated in the ocean, which eventually reached the consistency of "hot diluted broth". According to Haldane, the primitive atmosphere of the Earth was anaerobic (free of oxygen), but he did not claim that reducing conditions were required for the synthesis of organic compounds. Thus, he assumed that carbon could be present in the atmosphere in a fully oxidized form, that is, in the form of dioxide, and not in the composition of methane or other hydrocarbons. At the same time, Haldane referred to the results of experiments (not his own), in which the possibility of the formation of complex organic compounds from a mixture of carbon dioxide, ammonia and water under the influence of ultraviolet radiation was proved. However, in the future, all attempts to repeat these experiments were unsuccessful.

In 1952, Harold Urey (1893-1981), dealing not with the actual problems of the origin of life, but with the evolution of the solar system, independently came to the conclusion that the atmosphere of the young Earth had a restored character. Oparin's approach was qualitative. The problem that Urey was investigating was physico-chemical in nature: using as a starting point data on the composition of the primary cosmic dust cloud and the boundary conditions determined by the known physical and chemical properties of the moon and planets, he set out to develop a thermodynamically acceptable history of the entire solar system generally. Yuri, in particular, showed that by the end of the formation process, the Earth had a highly reduced atmosphere, since its main components were hydrogen and fully reduced forms of carbon, nitrogen and oxygen: methane, ammonia and water vapor. The gravitational field of the Earth could not hold light hydrogen - and it gradually disappeared into space. A secondary consequence of the loss of free hydrogen was the gradual oxidation of methane to carbon dioxide, and ammonia to gaseous nitrogen, which after a certain time turned the atmosphere from reducing to oxidizing. Yuri suggested that it was during the period of hydrogen volatilization, when the atmosphere was in an intermediate redox state, that complex organic matter could have formed on Earth in large quantities. According to his estimates, the ocean, apparently, was then a 1% solution of organic compounds. The result was life in its most primitive form.

It is believed that the solar system was formed from a pro-solar nebula - a huge cloud of gas and dust. The age of the Earth, as established on the basis of a number of independent estimates, is close to 4.5 billion years. To find out the composition of the primordial nebula, it is most reasonable to investigate the relative abundances of various chemical elements in the modern solar system. According to research, the main elements, hydrogen and helium, together make up over 98% of the mass of the Sun (99.9% of its atomic composition) and, in fact, the solar system as a whole. Since the Sun is an ordinary star and many stars in other galaxies belong to this type, its composition generally characterizes the abundance of elements in outer space. Modern concepts of stellar evolution suggest that hydrogen and helium also prevailed in the “young” Sun, which it was 4.5 billion years ago.

The four main elements of the Earth are among the nine most common on the Sun, in its composition our planet differs significantly from outer space as a whole. (The same can be said for Mercury, Venus, and Mars; however, Jupiter, Saturn, Uranus, and Neptune are not included in this list.) Earth is made up primarily of iron, oxygen, silicon, and magnesium. An obvious deficiency of all biologically important light elements (with the exception of oxygen) and striking according to the Oparin-Yuri theory, are necessary for the beginning of chemical evolution. Given the deficiency of light elements and especially noble gases, it is reasonable to assume that the Earth initially formed without an atmosphere at all. With the exception of helium, all noble gases - neon, argon, krypton, and xenon - have sufficient specific gravity to be held by gravity. Krypton and xenon, for example, are heavier than iron. Since these elements form very few compounds, they apparently existed in the primitive atmosphere of the Earth in the form of gases and could not escape when the planet finally reached its current size. But since there are millions of times less of them on the Earth than on the Sun, it is natural to assume that our planet has never had an atmosphere similar in composition to that of the Sun. The earth was formed from solid materials that contained only a small amount of absorbed or adsorbed gas, so there was no atmosphere at first. The elements that make up the modern atmosphere, apparently, appeared on the primitive Earth in the form of solid chemical compounds; subsequently, under the influence of heat arising from radioactive decay or the release of gravitational energy accompanying the accretion of the Earth, these compounds decomposed with the formation of gases. In the course of volcanic activity, these gases burst out of the earth's interior, forming a primitive atmosphere.

The high content of argon in the modern atmosphere (about 1%) does not contradict the assumption that noble gases were originally absent in the atmosphere. The isotope of argon, which is widespread in outer space, has an atomic mass of 36, while the atomic mass of argon, formed in the earth's crust during the radioactive decay of potassium, is 40. the element is capable of combining with many other elements, forming such very stable solid compounds, such as silicates and carbonates, which are part of rocks.

Yuri's assumptions about the reductive nature of the primitive atmosphere were based on the high content of iron on Earth (35% of the total mass). He believed that iron, of which the Earth's core now consists, was originally distributed more or less evenly throughout its entire volume. When the Earth warmed up, iron melted and collected in its center. However, before this happened, the iron contained in the layer of the planet now called the upper mantle of the Earth interacted with water (it was present on primitive Earth in the form of hydrated minerals, similar to those found in some meteorites); as a result, huge amounts of hydrogen were released into the primitive atmosphere.

Research carried out since the early 1950s has called into question a number of aspects of the scenario described. Some planetary scientists have expressed doubts about the fact that iron, now concentrated in the earth's crust, could ever be evenly distributed throughout the entire volume of the planet. They are inclined to believe that accretion was uneven and iron condensed from the nebula earlier than other elements that now form the mantle and crust of the Earth. With uneven accretion, the content of free hydrogen in the primitive atmosphere should have been lower than in the case of a uniform process. Other scientists have a preference for accretion, but it proceeds in a way that should not lead to the formation of a reducing atmosphere. In short, in recent years various models of the formation of the Earth have been analyzed, some of which to a greater extent, others to a lesser extent, agree with the ideas about the reductive nature of the early atmosphere.

Attempts to reconstruct the events that took place at the dawn of the formation of the solar system are inevitably associated with many uncertainties. The time interval between the emergence of the Earth and the formation of the most ancient rocks, amenable to geological dating, during which the chemical reactions that led to the emergence of life took place, is 700 million years. Laboratory experiments have shown that the synthesis of the components of the genetic system requires a regenerative environment; Therefore, we can say that once life arose on Earth, this can mean the following: either the primitive atmosphere had a reducing character, or the organic compounds necessary for the origin of life were brought to Earth from somewhere. Since even today meteorites bring a variety of organic matter to Earth, the latter possibility does not look absolutely fantastic. However, meteorites, apparently, do not contain all the substances necessary to build a genetic system. Although meteoric substances probably made a significant contribution to the general pool of organic compounds on primitive Earth, it currently seems most likely that conditions on Earth itself were reductive to such an extent that the formation of organic matter that led to the emergence of life became possible.

Modern biologists have shown that life is a chemical phenomenon that differs from other chemical processes in the manifestation of genetic properties. In all known living systems, nucleic acids and proteins serve as carriers of these properties. The similarity of nucleic acids, proteins and genetic mechanisms working on their basis in organisms of a wide variety of species leaves little doubt that all living things now living on Earth are linked by an evolutionary chain that also connects them with past and extinct species. Such evolution is a natural and inevitable result of the work of genetic systems. Thus, despite the endless variety, all living things on our planet belong to the same family. In fact, there is only one form of life on Earth, which could arise only once.

The main element of terrestrial biochemistry is carbon. The chemical properties of this element make it especially suitable for the formation of the type of large information-rich molecules that are necessary for the construction of genetic systems with practically unlimited evolutionary possibilities. Space is also very rich in carbon, and a number of data (the results of laboratory experiments, analyzes of meteorites and spectroscopy of interstellar space) indicate that the formation of organic compounds, like those that are part of living matter, occurs quite easily and on a large scale in the Universe. Therefore, it is likely that if life exists in some other corner of the universe, then it is also based on the chemistry of carbon.

Biochemical processes based on the chemistry of carbon can only take place when certain conditions of temperature and pressure are combined on the planet, as well as the presence of a suitable source of energy, atmosphere and solvent. Although water plays the role of a solvent in terrestrial biochemistry, it is possible, although not necessary, that other solvents are involved in biochemical processes occurring on other planets.

Criteria for the possibility of the origin of life

1.Temperature and pressure

If the assumption that life should be based on carbon chemistry is correct, then the limiting conditions for any environment capable of supporting life can be accurately set. First of all, the temperature should not exceed the limit of stability of organic molecules. Determining the temperature limit is not easy, but precise numbers are not required. Since temperature effects and pressure magnitude are interdependent, they should be considered together. Taking the pressure equal to about 1 atm (as on the surface of the Earth), it is possible to estimate the upper temperature limit of life, given that many small molecules from which the genetic system is built, for example, amino acids, are rapidly destroyed at temperatures of 200-300 ° C. Based on this, we can conclude that areas with temperatures above 250 ° C are uninhabited. (This, however, does not mean that life is determined only by amino acids; we have chosen them only as typical representatives of small organic molecules.) The real temperature limit of life should almost certainly be lower than indicated, since large molecules with a complex three-dimensional structure, in particular proteins built from amino acids are generally more sensitive to heat than small molecules. For life on the Earth's surface, the upper temperature limit is close to 100 ° C, and some types of bacteria can survive in hot springs under these conditions. However, the vast majority of organisms die at this temperature.

It may seem strange that the upper temperature limit for life is close to the boiling point of water. Is this coincidence due precisely to the fact that liquid water cannot exist at temperatures above its boiling point (100 ° C on the earth's surface), and not by some special properties of living matter itself?

Many years ago, Thomas D. Brock, an expert on thermophilic bacteria, suggested that life could be found wherever liquid water exists, regardless of its temperature. To raise the boiling point of water, you need to increase the pressure, as happens, for example, in an airtight pressure cooker. Enhanced heating makes the water boil faster without changing its temperature. The natural conditions in which liquid water exists at temperatures above its normal boiling point are found in areas of underwater geothermal activity, where superheated water is poured out of the earth's interior under the combined action of atmospheric pressure and the pressure of the ocean water layer. In 1982, KO Stetter discovered bacteria at a depth of up to 10 m in the zone of geothermal activity, for which the optimum temperature for development was 105 ° C. Since the pressure under water at a depth of 10 m is equal to 1 atm, the total pressure at this depth reached 2 atm. The boiling point of water at this pressure is 121 ° C.

Indeed, measurements showed that the water temperature in this place was 103 ° C. Therefore, life is possible at temperatures above the normal boiling point of water.

Obviously, bacteria that can exist at temperatures around 100 ° C have a “secret” that ordinary organisms lack. Since these thermophilic forms grow poorly at low temperatures or do not grow at all, it is fair to assume that ordinary bacteria have their own “secret”. The key property that determines the ability to survive at high temperatures is the ability to produce thermostable cellular components, especially proteins, nucleic acids and cell membranes. At temperatures of about 60 ° C, proteins of ordinary organisms undergo rapid and irreversible structural changes, or denaturation. An example is the coagulation of egg albumin (egg “white”) during cooking. Proteins from hot spring bacteria do not experience such changes up to 90 ° C. Nucleic acids are also susceptible to heat denaturation. In this case, the DNA molecule is divided into its two constituent strands. This usually occurs in the temperature range 85-100 ° C, depending on the ratio of nucleotides in the DNA molecule.

Denaturation destroys the three-dimensional structure of proteins (unique for each protein), which is necessary for its functions such as catalysis. This structure is supported by a whole set of weak chemical bonds, as a result of which the linear sequence of amino acids, which forms the primary structure of the protein molecule, fits into a special conformation characteristic of the given protein. The bonds supporting the three-dimensional structure are formed between amino acids located in different parts of the protein molecule. Mutations of the gene, which contains information about the amino acid sequence characteristic of a certain protein, can lead to changes in the composition of amino acids, which in turn often affects its thermal stability. This phenomenon opens up possibilities for the evolution of thermostable proteins. The molecular structure that ensures the thermostability of nucleic acids and cell membranes of bacteria living in hot springs is apparently also genetically determined.

Since the increase in pressure prevents water from boiling at its normal boiling point, it can prevent some of the damage to biological molecules associated with exposure to high temperatures. For example, a pressure of several hundred atmospheres suppresses the thermal denaturation of proteins. This is due to the fact that denaturation causes the unwinding of the helical structure of the protein molecule, accompanied by an increase in volume. By inhibiting the increase in volume, the pressure prevents denaturation. At much higher pressures, 5000 atm or more, it itself becomes the cause of denaturation. The mechanism of this phenomenon, which involves the compression destruction of the protein molecule, is not yet clear. Exposure to very high pressure also leads to an increase in the thermal stability of small molecules, since high pressure prevents the increase in volume due in this case to breaking of chemical bonds. For example, at atmospheric pressure, urea rapidly decomposes at a temperature of 130 ° C, but is stable for at least an hour at 200 ° C and a pressure of 29 thousand atm.

Molecules in solution behave completely differently. When interacting with a solvent, they often decompose at high temperatures. The general name for such reactions is solvation; if water is the solvent, the reaction is called hydrolysis.

Hydrolysis is the main process due to which proteins, nucleic acids and many other complex biological molecules are destroyed in nature. Hydrolysis occurs, for example, during digestion in animals, but it also occurs outside living systems, spontaneously, especially at high temperatures. Electric fields arising during solvolytic reactions lead to a decrease in the volume of the solution by electrostriction, i.e. binding adjacent solvent molecules. Therefore, one should expect that high pressure should accelerate the process of solvolysis, and experiments confirm this.

Since we believe that vital processes can only take place in solutions, it follows that high pressure cannot raise the upper temperature limit of life, at least in polar solvents such as water and ammonia. A temperature of about 100 ° C is probably a natural limit. As we will see, this excludes many planets of the solar system from consideration as possible habitats.

2. Atmosphere

The next condition necessary for the habitability of the planet is the presence of an atmosphere. Sufficiently simple compounds of light elements, which, according to our assumptions, form the basis of living matter, are usually volatile, that is, they are in a gaseous state over a wide temperature range. Apparently, such compounds are necessarily produced in metabolic processes in living organisms, as well as during thermal and photochemical effects on dead organisms, which are accompanied by the release of gases into the atmosphere. These gases, the simplest examples of which on Earth are carbon dioxide (carbon dioxide), water vapor and oxygen, are eventually included in the circulation of substances that occurs in living nature. If gravity could not hold them, then they would evaporate into outer space, our planet eventually exhausted its "reserves" of light elements and life on it would stop. Thus, if life appeared on some cosmic body, the gravitational field of which is not strong enough to hold the atmosphere, it could not exist for a long time.

It has been suggested that life may exist below the surface of celestial bodies such as the Moon, which either have a very thin atmosphere or lack it altogether. This assumption is based on the fact that gases can be captured by the subsurface layer, which becomes the natural habitat of living organisms. But since any habitat that has arisen under the surface of the planet is devoid of the main biologically important source of energy, the Sun, such an assumption only replaces one problem with another. Life needs a constant flow of both matter and energy, but if matter participates in the circuit (this is the reason for the need for an atmosphere), then energy, according to the fundamental laws of thermodynamics, behaves differently. The biosphere is able to function as long as it is supplied with energy, although its various sources are not equal. For example, the solar system is very rich in thermal energy - heat is generated in the bowels of many planets, including the Earth. However, we do not know organisms that would be able to use it as a source of energy for their life processes. To use heat as an energy source, the body probably must function like a heat engine, that is, transfer heat from an area of ​​high temperature (for example, from a cylinder of a gasoline engine) to an area of ​​low temperature (to a radiator). In this process, part of the transferred heat is transferred to work. But for the efficiency of such heat engines to be high enough, a high temperature of the “heater” is required, and this immediately creates enormous difficulties for living systems, since it gives rise to many additional problems.

None of these problems are caused by sunlight. The sun is a constant, virtually inexhaustible source of energy that is easily used in chemical processes at any temperature. Life on our planet is entirely dependent on solar energy, so it is natural to assume that nowhere else in the solar system could life develop without direct or indirect consumption of this type of energy.

The fact that some bacteria are able to live in the dark, using only inorganic substances for nutrition, and its dioxide as the only source of carbon, does not change the essence of the matter. Such organisms, called chemolithoautotrophs (which literally means: feeding themselves with inorganic chemicals), receive the energy necessary to convert carbon dioxide into organic matter through the oxidation of hydrogen, sulfur, or other inorganic substances. But these energy sources, unlike the Sun, are depleted and, after use, cannot be restored without the participation of solar energy. Thus, hydrogen, an important source of energy for some chemolithoautotrophs, is formed under anaerobic conditions (for example, in swamps, at the bottom of lakes, or in the gastrointestinal tract of animals) by decomposition of plant material under the action of bacteria, which itself, of course, is formed during photosynthesis. Chemolithoautotrophs use this hydrogen to produce methane and substances necessary for the life of the cell from carbon dioxide. Methane is released into the atmosphere where it is decomposed by sunlight to form hydrogen and other products. In the Earth's atmosphere, hydrogen is contained in a concentration of 0.5 parts per million; almost all of it was formed from methane released by bacteria. Hydrogen and methane are also emitted into the atmosphere during volcanic eruptions, but in incomparably smaller quantities. Another significant source of atmospheric hydrogen is the upper atmosphere, where, under the influence of solar UV radiation, water vapor decomposes with the release of hydrogen atoms, which escape into space.

Numerous populations of various animal fish, sea molluscs, mussels, giant worms, etc., which have been found to live near the hot springs found at a depth of 2500 m in the Pacific Ocean, are sometimes credited with the ability to exist independently of solar energy. Several such zones are known: one near the Galapagos archipelago, the other at a distance of about 21 ° to the northwest, off the coast of Mexico. In the depths of the ocean, food reserves are notoriously scarce, and the discovery in 1977 of the first such population immediately raised the question of the source of their food. One possibility seems to be the use of organic matter accumulating on the ocean floor, waste products generated by biological activity in the surface layer; they are transported to areas of geothermal activity by horizontal currents resulting from vertical emissions of hot water. The upward movement of superheated water causes the formation of bottom horizontal cold currents directed to the place of discharge. It is assumed that organic remains accumulate here in this way.

Another source of nutrients became known after it was discovered that the water of thermal springs contains hydrogen sulfide (H 2 S). It is possible that chemolithoautotrophic bacteria are located at the beginning of the food chain. Further studies showed that chemolithoautotrophs are indeed the main source of organic matter in the ecosystem of thermal springs.

Since the hydrogen sulfide formed in the depths of the Earth serves as the "fuel" for these deep-sea communities, they are usually considered as living systems that can do without solar energy. However, this is not entirely true, since the oxygen they use to oxidize the “fuel” is a product of photochemical transformations. There are only two significant sources of free oxygen on Earth, and both are associated with the activity of the Sun.

The ocean plays an important role in the life of the deep-sea ecosystem, as it creates an environment for organisms from thermal springs, without which they could not exist. The ocean provides them not only with oxygen, but also with all the necessary nutrients, with the exception of hydrogen sulfide. It removes waste. And it also allows these organisms to move to new areas, which is necessary for their survival, since the sources are short-lived - according to estimates, their lifespan does not exceed 10 years. The distance between individual thermal springs in one area of ​​the ocean is 5-10 km.

3. Solvent

At present, it is generally accepted that the presence of a solvent of one type or another is also a necessary condition for life. Many chemical reactions in living systems would not be possible without a solvent. On Earth, such a biological solvent is water. It is the main component of living cells and one of the most common compounds on the earth's surface. Due to the fact that the chemical elements that form water are widespread in outer space, water is undoubtedly one of the most common compounds in the universe. But despite such an abundance of water everywhere. Earth is the only planet in the solar system with an ocean on its surface; this is an important fact that we will come back to later.

Water has a number of special and unexpected properties, thanks to which it can serve as a biological solvent - the natural habitat of living organisms. These properties determine its main role in stabilizing the Earth's temperature. These properties include: high melting (melting) and boiling points; high heat capacity; a wide range of temperatures within which water remains in a liquid state; large dielectric constant (which is very important for a solvent); the ability to expand near the freezing point. These issues were comprehensively developed, in particular, in the works of L.J. Henderson (1878-1942), professor of chemistry at Harvard University.

Modern research has shown that such unusual properties of water are due to the ability of its molecules to form hydrogen bonds with each other and with other molecules containing oxygen or nitrogen atoms. In reality, liquid water is made up of aggregates in which individual molecules are linked together by hydrogen bonds. For this reason, when discussing the question of which non-aqueous solvents could be used by living systems in other worlds, special attention is paid to ammonia (NH 3), which also forms hydrogen bonds and is similar in many properties to water. Other substances capable of forming hydrogen bonds are also named, in particular hydrofluoric acid (HF) and hydrogen cyanide (HCN). However, the last two connections are unlikely candidates for this role. Fluorine is one of the rare elements: there are 10,000 oxygen atoms per fluorine atom in the observable Universe, so it is difficult to imagine conditions on any planet that would favor the formation of an ocean consisting of HF rather than H2O. As for hydrogen cyanide (HCN ), its constituent elements in outer space are found in abundance, but this compound is not thermodynamically stable enough. Therefore, it is unlikely that it could ever accumulate in large quantities on any planet, although, as we said earlier, HCN is an important (albeit temporary) intermediate in the prebiological synthesis of organic substances.

Ammonia is composed of fairly common elements and, although less stable than water, it is still stable enough to be considered a possible biological solvent. At a pressure of 1 atm, it is in a liquid state in the temperature range 78 - 33 ° C. This range (45 °) is much narrower than the corresponding range for water (100 ° C), but it covers the region of the temperature scale where water cannot function as a solvent. Considering ammonia, Gender-sleep pointed out that this is the only known compound that, as a biological solvent, approaches water in its properties. But in the end, the scientist retracted his statement for the following reasons. First, ammonia cannot accumulate in sufficient quantities on the surface of any planet; secondly, unlike water, it does not expand at a temperature close to the freezing point (as a result of which its entire mass can remain entirely in a solid, frozen state), and finally, its choice as a solvent excludes the benefits of using oxygen as a biological reagent ... Gen-Derson did not express a definite opinion about the reasons that would prevent ammonia from accumulating on the surface of the planets, but nevertheless he was right. Ammonia is destroyed by UV radiation from the Sun more easily than water, that is, its molecules are degraded by radiation of a longer wavelength, carrying less energy, which is widely represented in the solar spectrum. The hydrogen formed in this reaction escapes from the planets (with the exception of the largest ones) into outer space, and the nitrogen remains. Water is also destroyed in the atmosphere by solar radiation, but only at a much shorter wavelength than that which destroys ammonia, and the oxygen (O 2) and ozone (O 3) released during this form a shield that very effectively protects the Earth from the deadly UV radiation. -radiation. Thus, self-limitation of photodestruction of atmospheric water vapor occurs. In the case of ammonia, this phenomenon is not observed.

This reasoning does not apply to planets like Jupiter. Since hydrogen is abundant in the atmosphere of this planet, being its constant component, it is reasonable to assume the presence of ammonia there. These assumptions are confirmed by spectroscopic studies of Jupiter and Saturn. It is unlikely that there is liquid ammonia on these planets, but the existence of ammonia clouds consisting of frozen crystals is quite possible.

Considering the issue of water in a broad sense, we have no right to a priori affirm or deny that water as a biological solvent can be replaced by other compounds. When discussing this problem, there is often a tendency to simplify it, since, as a rule, only the physical properties of alternative solvents are taken into account. At the same time, the fact that Henderson noted, namely: water serves not only as a solvent, but also as an active participant in biochemical reactions, is underestimated or completely ignored. The elements that make up water are “incorporated” into the substances of living organisms by hydrolysis or photosynthesis in green plants (see reaction 4). The chemical structure of a living substance based on a different solvent, like the entire biological environment, must necessarily be different. In other words, changing a solvent will inevitably have extremely profound consequences. Nobody seriously tried to imagine them. Such an attempt is hardly reasonable, for it is nothing more and nothing less than a blueprint for a new world, and this is a highly dubious business. So far we are not able to answer even the question of the possibility of life without water, and we hardly know anything about it until we find an example of waterless life.

Can it explode

Black Sea?

In 1891, Professor A. Lebedintsev raised the first water sample from the depths of the Black Sea. The test showed that the water below 183 meters is saturated with hydrogen sulfide. Subsequent studies have confirmed that the Black Sea is the world's largest hydrogen sulfide basin. 3500 - 4000 years ago the Strait of Gibraltar did not exist, and the Mediterranean Sea was divided into two basins: the Outer Sea to the west of Sicily and the Inland Sea to the east of it. The levels of these seas were significantly lower than the modern ones. At that time, the Black Sea (Euxine Pontus) was freshwater, and the main supply of these seas went through the Bosporus (Bosphorus) due to the greater flow of the rivers of the Black Sea basin. 3500 years ago, significant movements of the crust of Europe took place in a westerly direction, the Strait of Gibraltar was formed, and the salty water of the ocean raised the levels of these seas to the present day.

The richest freshwater flora and fauna of the Black Sea perished and sank to the bottom. The decomposition of protein substances at the bottom saturated the bottom waters with hydrogen sulfide and methane. After this event, the level of hydrogen sulfide rose, and nowadays it is kept at a depth of 200 - 100 meters. In August 1982, in the eastern part of the sea, hydrogen sulfide was discovered at a depth of 60 meters, and the diameter of the "dome" of its rise reached 120 km. In autumn, the level of hydrogen sulfide dropped to 150 meters. This indicates a significant release of hydrogen sulfide from the depths as a result of an earthquake on the seabed.

There are various hypotheses regarding the reasons for the containment of hydrogen sulfide at depth. According to some scientists, dissolved hydrogen sulfide restrains only a significant pressure of the overlying water layers (10-20 atmospheres). If this "plug" is removed, the water will "boil" and hydrogen sulfide will rapidly evolve from it in the form of a gas (by analogy with a bottle of sparkling water).

10 years ago, as a result of an earthquake in the area of ​​a small African lake, hydrogen sulfide was released from it. The gas spread in a two-three-meter layer along the banks, which led to the death of all living things from suffocation. I also remember the story of eyewitnesses to the 1927 Crimean earthquake. Then a thunderstorm broke out, and tongues of flame appeared in the sea to the surprised gaze of the inhabitants of Yalta - the sea caught fire! Thus, the presence of hydrogen sulfide in the Black Sea poses a very serious danger to the population of the countries of its basin.

This danger is especially great for coastal areas with low relief marks, for example, Colchis. In Colchis, earthquakes of high magnitude occurred in 1614 (destruction of the Tsaish complex), in 1785, 1905, 1958 and in 1959. Fortunately, none of them touched the seabed. Much more dangerous is the situation in Crimea (Crimea has a tendency to slide towards the sea) and along the coast of Turkey, which has mobile crustal faults. There is only one way to reduce the danger of the Black Sea "explosion" through the intensive economic use of hydrogen sulfide as a fuel. Pumping deep water through sedimentation tanks will give unlimited volumes of gas that can be used in thermal power plants with explosion-proof dosing. With such a centralized combustion of hydrogen sulfide, it is possible to solve the issue of using sulfur-containing combustion waste without harming the environmental situation. The international conference "Eco - Black Sea-90" painted a threatening picture of anthropogenic pressure on the ecosystem of the sea - only the Danube and the Dnieper annually carry 30 tons of mercury and other poisons into the sea. The fish stocks of the sea have decreased tenfold. With regard to the Mediterranean Sea, the Blue Plan is being implemented under the auspices of the United Nations. 110 universities and other organizations in Europe are connected to it. Only the Black Sea does not have a single plan of salvation. And he is urgently needed.

Reasons for the formation of hydrogen sulfide in water.

Hydrogen sulfide and sulfur compounds, sulfides and other reduced forms of sulfur are not typical and permanent components of sea waters.

However, under certain conditions, hydrogen sulfide and sulfides can accumulate in the deep layers of the sea in significant quantities. Areas with a sufficiently high hydrogen sulfide content can sometimes form even at shallow depths. But the temporary accumulation of hydrogen sulfide in the sea is also undesirable, since its appearance causes the death of the marine fauna. At the same time, the presence of hydrogen sulfide in seawater serves as a characteristic indicator of certain hydrological conditions, as well as intensive consumption of dissolved oxygen and the presence of a large amount of easily oxidized substances of various origins.

The main source of hydrogen sulfide in the sea is the biochemical reduction of dissolved sulfates (desulfation process). Desulfation in the sea is caused by the vital activity of a special type of anaerobic desulfating bacteria, which reduce sulfates to sulfides, the latter being decomposed by dissolved carbonic acid to hydrogen sulfide. This process can be schematically represented as follows:

CaS + NaCO 3 → CaCO 3 + H 2 S.

In reality, this process is more complicated, and not only free hydrogen sulfide is present in the hydrogen sulfide zone, but also other forms of sulfate reduction products (sulfides, hydrosulfites, hyposulfites, etc.).

In hydrochemical practice, the content of reduced forms of sulfur compounds is usually expressed in the equivalent of hydrogen sulfide. Only in special specially designed studies are the various reduced forms of sulfur determined separately. These definitions are not covered here.

The second source of hydrogen sulfide in the sea is the anaerobic decay of sulfur-rich protein organic residues of dead organisms. Sulfur-containing proteins, when decomposed in the presence of a sufficient amount of dissolved oxygen, are oxidized, and the sulfur contained in them is converted into a sulfate ion. Under anaerobic conditions, the decomposition of sulfur-containing protein substances leads to the formation of mineral forms of sulfur, i.e., hydrogen sulfide and sulfides.

Cases of temporary occurrence of anaerobic conditions and the associated accumulation of hydrogen sulfide are observed in the Baltic and Azov seas, as well as in some bays and bays of other seas. A classic example of a sea basin contaminated with hydrogen sulfide is the Black Sea, where only the upper relatively thin surface layer is free of hydrogen sulfide.

Hydrogen sulfide and sulfides that arise under anaerobic conditions are easily oxidized when dissolved oxygen enters, for example, during wind mixing of the upper, well-aerated layers of water with deep waters contaminated with hydrogen sulfide. Since even a temporary accumulation of hydrogen sulfide and sulfur compounds in the sea is of significant importance as an indicator of water pollution and the possibility of the occurrence of marine fauna kills, observations of its appearance are absolutely necessary in the study of the hydrochemical regime of the sea.

In total, there are 2 main methods for determining the amount and concentration of hydrogen sulfide in the Black Sea: Volumetric analytical method and Colorimetric method, but these methods are not metrologically certified.

Hydrogen sulfide boom.

As mentioned earlier, a feature of the Black Sea is the presence of a "hydrogen sulphide layer" in it. It was discovered a hundred years ago by a Russian boatswain, having sniffed a rope lowered to a depth, from which it smelled slightly of rotten eggs. The level of the "hydrogen sulfide layer" fluctuates, sometimes its boundary rises to a depth of only 50 m. In 1927, during the great earthquake, there were even "sea fires", and columns of flame were observed in the sea near Sevastopol and Yevpatoria.

Perestroika in the USSR coincided with another rise in the hydrogen sulphide layer, and glasnost gave newspapers spicy information about the "sea fires" of 1927 (before, when there was no habit of frightening people, this information was not widely published). The conditions were favorable for a major boom, and it was "promoted". Here are examples of hysterical forecasts for 1989-1990. only in central newspapers:

"Literaturnaya gazeta": "What will happen if, God forbid, a new earthquake happens off the Black Sea shores? Sea fires again? Or one flash, one grand torch? Hydrogen sulfide is flammable and poisonous, hundreds of thousands of tons of sulfuric acid appear in the sky."

"Working tribune": "A small earthquake is enough for hydrogen sulfide to come to the surface of the Black Sea and catch fire - and its coast will turn into a desert."

"Top secret": "The coincidence in time and space of a sharp drop in atmospheric pressure and a vertical current is enough. Having boiled, the water will saturate the air with poisonous vapors of combustible gas. Where the deadly cloud will drift - God only knows. It can cause casualties on the coast, maybe in a matter of seconds. turn a passenger liner into a "Flying Dutchman" in seconds.

Finally, Mikhail Gorbachev himself warned the world about the impending apocalypse from the USSR. He said from the rostrum of the International Global Forum on Environmental Protection and Development for Survival (what is the name of the forum!): “The upper boundary of the hydrogen sulfide layer in the Black Sea has risen from a depth of 200 m to 75 m from the surface over the past decades. the threshold of the Bosphorus, it will go to the Marmara, Aegean and Mediterranean seas. " This statement was published in Pravda. Scientists - both oceanographers and chemists - tried to explain to politicians that all this is an ignorant delirium (so they naively thought). Well-known data have been published in scientific journals:

1. "Sea fires" in 1927 have nothing to do with hydrogen sulfide. They were observed in places located 60-200 km from the border of the hydrogen sulfide zone. Their reason is the emergence of natural gas methane from the Krivoy Rog-Evpatoria tectonic fault during an earthquake. This is a gas-bearing region, drilling for gas production is underway, and natural gas outflows in this water area in the form of "flares" are observed regularly. All this is well known, and the refusal of all the major newspapers to publish this scholarly report directly indicates that it was a deliberate misinformation.

2. The maximum concentration of hydrogen sulfide in the Black Sea water is 13 mg per liter, which is 1000 times less than necessary for it to be released from the water in the form of gas. A thousand times! Therefore, there can be no question of any ignition, devastation of the coast and burning of liners. For hundreds of years, people have been using the hydrogen sulfide springs of Matsesta for medicinal purposes (perhaps even Mikhail Gorbachev himself enjoyed them). They did not hear about any explosions and fires, even the smell of hydrogen sulfide is quite tolerable there. But the content of hydrogen sulfide in the waters of Matsesta is hundreds of times higher than in the water of the Black Sea. There have been cases when people met high concentration hydrogen sulfide jets in mines. This led to the poisoning of people, but there were never and could not have been explosions - the threshold explosive concentration of hydrogen sulfide in the air is very high.

3. The lethal concentration of hydrogen sulfide in the air is 670-900 mg per cubic meter. But already at a concentration of 2 mg per cubic meter, the smell of hydrogen sulfide is unbearable. But even if the entire "hydrogen sulphide layer" of the Black Sea is suddenly thrown to the surface by some unknown force, the content of hydrogen sulphide in the air will be many times lower than the level unbearable by smell. This means that it is thousands of times lower than the level that is dangerous to health. So there can be no talk of poisoning either.

4. Mathematical modeling of all conceivable regimes in the fluctuation of the world ocean level and atmospheric pressure over the Black Sea, carried out by oceanologists in connection with the statement of M.S. absolutely impossible - even if the most powerful of the known tropical cyclones passes over Yalta.

All this was thoroughly known, the hydrogen sulfide anomaly of the Black Sea has been studied for a hundred years by many scientists around the world. When the Soviet press began this boom, a number of reputable scientists, including academicians (!), Turned to the newspapers - none of them undertook to provide reassuring information. The most popular publication that we managed to get through is the journal of the Academy of Sciences of the USSR "Priroda", a journal for scientists. But he could not compare with the circulation of Pravda, Literaturnaya Gazeta, Ogonyok of that time, or with the influence of television.

A group of oceanologists (T. A. Aizatulin, D. Ya. Fashchuk and A. V. Leonov) shrewdly concludes one of the last articles devoted to the problem in the "Journal of the All-Union Chemical Society" (No. 4, 1990): "Working in cooperation with prominent foreign researchers, eight generations of Russian scientists have accumulated vast knowledge about the hydrogen sulfide zone of the Black Sea, and all this knowledge accumulated over a century turned out to be unclaimed and unnecessary.

This substitution is not just another evidence of the crisis in the social sphere, to which science belongs. Due to a number of peculiarities, this, in our opinion, is a clear indicator of a social catastrophe. The peculiarities are that at all levels reliable quantitative knowledge about a very specific, unambiguously measured object, about which there is no disagreement in the world scientific community in essence, is replaced by a myth that is dangerous in its consequences. This knowledge is easily monitored using commonly available measurement tools such as rope and boatswain's bow. Information about it is easy to obtain within ten minutes - an hour using ordinary information channels or by phone call to any institute of oceanological profile of the USSR Academy of Sciences, Hydrometeorological Service or the Ministry of Fisheries. And if, in relation to such a completely definite knowledge, it turned out to be possible to substitute myths, then we must expect it necessarily in such areas of contradictory and ambiguous knowledge as economics and politics.

Many crises in which our society is plunging represent a swamp of artificial origin. You can only drown in it while lying down. To give the topography of the crisis swamp in our area, to show the presence of the horizon, lifting a person from his belly to his feet, is the purpose of this review. "

As you know, it was not possible to lift the Soviet person "from his belly to his feet" in the artificially created swamp - the manipulators of consciousness who were interested and standing on their feet did not give it. Now we are studying this case already as pathologists - we are doing an autopsy. But the continuation is also very interesting - with a still living consciousness.

After the true goal of hydrogen sulfide psychosis (as part of a large program) was achieved, everyone suddenly forgot about hydrogen sulfide, as well as about factories of protein and vitamin supplements to poultry feed. But on July 7, 1997, just as suddenly, after many years of complete silence, there was another broadcast on television about the hydrogen sulfide threat. This time, delirium was launched into consciousness, leaving far behind the predictions of 1989. The explosion of all the hydrogen sulfide of the Black Sea was promised to be so powerful that it, like a detonator, would cause an atomic explosion of uranium, the deposits of which are in the Caucasus! Thus, hydrogen sulfide was linked to nuclear weapons - a symbol of modern danger.

So can the Black Sea explode or not?

The Azov-Black Sea basin at the beginning of the twentieth century was a unique geophysical formation: shallow fresh Azov and deep salty Black Sea. Most of the inhabitants of this basin in the spring went to spawn in the Sea of ​​Azov, and wintered in the Black Sea, which resembles a glass in its "cut": a narrow coastal strip abruptly breaks off to a depth of three kilometers.

The main suppliers of fresh water to the Azov-Black Sea basin are three rivers: Dnieper, Danube, Don. This water, mixing with salt water during storms, formed a two-hundred-meter habitable layer. Below this mark, biological organisms do not live in the Black Sea. The fact is that the Black Sea communicates with the world's oceans through the narrow Bosphorus strait. The warm, oxygen-enriched water of the Black Sea flows through this strait in the upper layer into the Mediterranean Sea. In the lower layer of the Bosphorus, colder and saltier water enters the Black Sea. This structure of water exchange over millions of years has led to the accumulation of hydrogen sulfide in the lower layers of the Black Sea. H 2 S is formed in water as a result of anoxic decomposition of biological organisms and has a characteristic smell of rotten eggs. Any aquarist knows very well that in a large aquarium, hydrogen sulfide gradually accumulates in the bottom layer as a result of decay of food residues and plants. The first indicator of this is that fish begin to swim in the near-surface layer. Further accumulation of H 2 S can lead to the death of the inhabitants of the aquarium. To remove hydrogen sulphide from the water, aquarists use artificial aeration: a microcompressor atomizes air into the lower layer of water. At the same time, over time, the sprayer and the soil near it becomes covered with a yellow coating - gray. Chemists know two types of hydrogen sulfide oxidation reaction:

1.H 2 S + O 2 → H 2 O + S

2.H 2 S + 4O 2 → H 2 SO 4

The first reaction produces free sulfur and water. As it accumulates, sulfur can float in small pieces to the surface.

The second type of H 2 S oxidation reaction proceeds explosively during the initial thermal shock. The result is sulfuric acid. Doctors sometimes have to deal with cases of intestinal burns in children - the consequences of a seemingly harmless prank. The fact is that intestinal gases contain hydrogen sulfide. When children "jokingly" set them on fire, the flames can enter the intestines. The result is not only thermal, but also acid burn.

It was the second course of the H 2 S oxidation reaction that the inhabitants of Yalta observed during the earthquake in 1927. Seismic shocks have stirred deep-sea hydrogen sulfide to the surface. The electrical conductivity of an aqueous solution of H 2 S is higher than that of pure seawater. Therefore, electrical lightning discharges most often fell precisely in the areas of hydrogen sulfide raised from the depths. However, a significant layer of pure surface water extinguished the chain reaction.

By the beginning of the 20th century, as already mentioned, the upper inhabited layer of water in the Black Sea was 200 meters. Thoughtless technogenic activity has led to a sharp reduction in this layer. At present, its thickness does not exceed 10-15 meters. During a strong storm, hydrogen sulfide rises to the surface, and vacationers can smell a characteristic smell.

At the beginning of the century, the Don River supplied up to 36 km3 of fresh water to the Azov-Black Sea basin. By the beginning of the 80s, this volume had decreased to 19 km 3: metallurgical industry, irrigation facilities, irrigation of fields, city water pipelines ... The commissioning of the Volga-Don nuclear power plant will take another 4 km 3 of water. A similar situation has occurred during the years of industrialization and on other rivers of the basin.

As a result of the thinning of the surface habitable layer of water, a sharp decrease in biological organisms took place in the Black Sea. For example, in the 50s, the dolphin population reached 8 million individuals. Nowadays, it has become a rarity to meet dolphins in the Black Sea. Fans of underwater sports sadly observe only remnants of pathetic vegetation and rare schools of fish. But this is not the worst thing!

If the Crimean earthquake happened today, then everything would end in a global catastrophe: billions of tons of hydrogen sulfide are covered by the thinnest water film. What is the scenario of a probable cataclysm?

As a result of the primary thermal shock, a volumetric explosion of H 2 S will occur. This can lead to powerful tectonic processes and movements of lithospheric plates, which, in turn, will cause destructive earthquakes around the globe. But that is not all! The explosion will release billions of tons of concentrated sulfuric acid into the atmosphere. These will not be modern weak acid rains after our factories and plants. Acid rains after the explosion of the Black Sea will burn out all life and inanimate on the planet! Or - almost everything ...

In 1976, a simple and cheap project was proposed. Its main meaning was as follows: the mountain rivers of the Caucasus bring fresh water from melting glaciers to the sea. Flowing along shallow rocky channels, the water is enriched with oxygen. Considering that the density of fresh water is less than that of salty water, the flow of a mountain river, flowing into the sea, spreads over its surface. If this water is let through a pipe to the bottom of the sea, then the situation of aeration of water in the aquarium is realized. This would require 4-5 km of pipes lowered to the bottom of the sea and a maximum of a couple of tens of kilometers of pipes to a small dam in the riverbed. The fact is that in order to balance the three-kilometer depth of salt water, fresh water must be supplied by gravity from a height of 80-100 meters. This will be a maximum of 10-20 km from the seashore. It all depends on the relief of the coastal area.

Several such aeration systems could initially stop the sea extinction process and, over time, lead to the complete neutralization of H 2 S in its depths. It is clear that this process would not only allow to revive the flora and fauna of the Azov-Black Sea basin, but also eliminate the possibility of a global catastrophe.

However, as practice shows, government agencies are completely uninterested in all this. Why invest, however small, money in a dubious measure to save the Earth from a global catastrophe? Although, aeration plants could provide "real money" - sulfur, released as a result of the oxidation of hydrogen sulfide.

But no one can say for sure when the Black Sea will explode. To predict in advance the possibility of its occurrence, it is necessary to organize tracking services for the processes of tectonic movements of the blocks of the earth's crust in this territory. Better still be prepared for such situations. After all, people live even at the foot of Vesuvius. Those who live within territories where such catastrophic events can occur should organize their way of life accordingly.

But this is not as scary as it seems at first glance. The previous explosion of the Black Sea took place several million years ago. In its evolution, the tectonic activity of the Earth calms down more and more. It is quite possible that the next explosion of the Black Sea will occur in a few million years. And this is already boundless time even for a simple human imagination.

One of the ways to use hydrogen sulfide.

Economists and power engineers come to the conclusion that in the near future there is nothing to replace nuclear power. Although after Chernobyl everyone recognizes its danger, especially for countries with an unstable situation and rampant terrorism. Unfortunately, Russia is also one of such countries today. Meanwhile, there is a real alternative to nuclear energy. In the archive of Yutkin L.A. there is a project that can now attract the attention of power engineers.

After the collapse of the USSR, Russia was left with a small section of the Black Sea coast. Yutkin L.A. called the Black Sea a unique natural storehouse with inexhaustible reserves of energy: the energy "Eldorado" with renewable sources of raw materials. The author of the electrohydraulic effect L.A. Yutkin sent his fantastic and at the same time quite real project to the State Committee for Inventions and the State Committee for Science and Technology of the USSR.

The project was based on gas separation and enrichment methods. The fact is that the waters of the Black Sea below a depth of 100 meters contain ... hydrogen sulphide dissolved in them. It is especially important that, unlike other fossil fuels, the reserves of hydrogen sulfide in the Black Sea are renewable. As studies have shown, and as mentioned earlier, the replenishment of hydrogen sulfide occurs due to two sources: the activity of microorganisms capable of reducing sulfate sulfur to sulfide in anaerobic conditions, and the influx of hydrogen sulfide synthesized in the depths of the Caucasus Mountains from cracks in the earth's crust. The concentration of hydrogen sulfide is regulated by its oxidation in the surface layers of water. Oxygen in the air, dissolving in water, interacts with hydrogen sulfide, converting it into sulfuric acid. The acid reacts with mineral salts dissolved in water to form sulfates. These processes are going on simultaneously, due to which a dynamic equilibrium is established in the Black Sea. Calculations show that during the year, as a result of oxidation in the Black Sea, no more than a quarter of all hydrogen sulfide is converted into sulfates.

Thus, from the Black Sea, without prejudice to its ecology, as well as lowering the chances of an “explosion” of the Black Sea, about 250 million tons of hydrogen sulphide with an energy intensity of about 10 12 kWh can be emitted annually (burning one kilogram of hydrogen sulphide gives about 4000 kcal.) ... This corresponds to the annual production of electricity in the former USSR and is twice that of Russia. Consequently, the Black Sea as a hydrogen sulfide generator can fully satisfy the domestic energy demand. How can this fantastic idea be put into practice?

To do this, Yutkin proposed to raise the bottom layers of seawater from areas of anomalously high hydrogen sulfide content to a technological height, where they should be exposed to electro-hydraulic shocks, which ensure the release of hydrogen sulfide, and then returned back to the sea (electro-hydraulic effect). The resulting gas must be liquefied and burned, and the resulting sulfur dioxide must be oxidized to sulfuric acid. When burning 1 kg of hydrogen sulphide, up to two kilograms of sulfur dioxide and 4 × 10 3 kcal of recovered heat can be obtained. Energy is also released when sulfur dioxide is oxidized to sulfuric acid. Each ton of hydrogen sulfide, when combusted, gives 2.9 tons of sulfuric acid. The additional energy arising from its synthesis will amount to 5 × 10 5 kcal for each ton of acid produced.

Calculations show that in order to meet all the needs of the CIS countries for electricity, without violating the ecology of the sea, it is necessary to allocate and burn 7,400 cubic meters annually. km of sea water. Combustion of 2 × 5 × 10 8 tons of hydrogen sulfide will make it possible to obtain 7 × 3 × 10 8 tons of sulfuric acid, the synthesis of which will produce an additional 3 × 6 × 10 14 kcal of heat or 4 × 1 × 10 11 kW / h of additional energy. This energy will provide all the work of the technological cycle - pumping water, electrohydraulic treatment of its processing, compression and liquefaction of the resulting gas.

The only "waste" of such power plants will be sulfuric acid - a valuable raw material for many other industries.

At the very beginning of the proposal for this project, it was banned for implementation.

Depletion of the ozone layer

In 1985, atmospheric researchers from the British Antarctic Survey reported a completely unexpected fact: the spring ozone content in the atmosphere over Halley Bay in Antarctica decreased by 40% between 1977 and 1984. Soon this conclusion was confirmed by other researchers, who also showed that the area of ​​low ozone content extends beyond Antarctica and covers a layer from 12 to 24 km in height, i.e. a significant part of the lower stratosphere. The most detailed study of the ozone layer over Antarctica was the International Aircraft Antarctic Ozone Experiment. In its course, scientists from 4 countries climbed several times into the area of ​​low ozone content and collected detailed information about its size and chemical processes taking place in it. In fact, this meant that there was an ozone "hole" in the polar atmosphere. In the early 1980s, according to measurements from the Nimbus-7 satellite, a similar hole was found in the Arctic, although it covered a much smaller area and the drop in ozone level in it was not so great - about 9%. On average over the Earth from 1979 to 1990, the ozone content fell by 5%.

This discovery worried both scientists and the general public, as it implied that the ozone layer surrounding our planet was in greater danger than previously thought. Thinning of this layer can lead to serious consequences for humanity. The ozone content in the atmosphere is less than 0.0001%, however, it is ozone that completely absorbs the hard ultraviolet radiation of the sun with a long wave<280 нм и значительно ослабляет полосу УФ-Б с 280< < нм, наносящие 315 серьезные поражения клеткам живых организмов. Падение концентрации озона на 1% приводит в среднем к увеличению интенсивности жесткого ультрафиолета у поверхности земли на 2%. Эта оценка подтверждается измерениями, проведенными в Антарктиде (правда, из-за низкого положения солнца, интенсивность ультрафиолета в Антарктиде все еще ниже, чем в средних широтах. По своему воздействию на живые организмы жесткий ультрафиолет близок к ионизирующим излучениям, однако, из-за большей, чем у -излучения длины волны он не способен проникать глубоко в ткани, и поэтому поражает только поверхностные органы. Жесткий ультрафиолет обладает достаточной энергией для разрушения ДНК и других органических молекул, что может вызвать рак кожи, в осбенности быстротекущую злокачественную меланому, катаракту и иммунную недостаточность. Естественно, жесткий ультрафиолет способен вызывать и обычные ожоги кожи и роговицы. Уже сейчас во всем мире заметно увеличение числа заболевания раком кожи, однако значительно количество других факторов (например, возросшая поулярность загара, приводящая к тому, что люди больше времени проводят на солнце, таким образом получая большую дозу УФ облучения) не позволяет однозначно утверждать, что в этом повинно уменьшение содержания озона. Жесткий ультрафиолет плохо поглощается водой и поэтому представляет большую опасность для морских экосистем. Эксперименты показали, что планктон, обитающий в приповерхностном слое при увеличении интенсивности жесткого УФ может серьезно пострадать и даже погибнуть полностью. Планктон накодится в основании пищевых цепочек практически всех морских экосистем, поэтому без приувеличения можно сказать, что практически вся жизнь в приповерхностных слоях морей и океанов может исчезнуть. Растения менее чуствительны к жесткому УФ, но при увеличении дозы могут пострадать и они.

The formation of ozone is described by the reaction equation:

The atomic oxygen required for this reaction above the level of 20 km is formed during the splitting of oxygen under the action of ultraviolet radiation with<240 нм.

Below this level, such photons hardly penetrate, and oxygen atoms are formed mainly during photodissociation of nitrogen dioxide by photons of soft ultraviolet radiation with<400 нм:

The destruction of ozone molecules occurs when they hit aerosol particles or the earth's surface, but the main ozone sink is determined by the cycles of catalytic reactions in the gas phase:

O 3 + Y → YO + O 2

YO + O → Y + O 2

where Y = NO, OH, Cl, Br

For the first time, the idea of ​​the danger of the destruction of the ozone layer was expressed back in the late 1960s, when it was believed that the main danger to the atmosphere was the emissions of water vapor and nitrogen oxides (NO) from the engines of supersonic transport aircraft and rockets. However, supersonic aviation developed at a much less rapid pace than anticipated. Currently, only the Concorde is used for commercial purposes, making several flights a week between America and Europe; from military aircraft in the stratosphere, practically only supersonic strategic bombers such as B1-B or Tu-160 and reconnaissance aircraft of the SR-71 type fly ... This load is unlikely to pose a serious threat to the ozone layer. Emissions of nitrogen oxides from the earth's surface from the burning of fossil fuels and the mass production and use of nitrogen fertilizers also pose some threat to the ozone layer, but nitrogen oxides are unstable and easily degraded in the lower atmosphere. Rocket launches also do not occur very often, however, chlorate solid propellants used in modern space systems, for example, in the Space Shuttle or Ariane solid-propellant boosters, can cause serious local damage to the ozone layer in the launch area.

In 1974 M. Molina and F. Rowland of the University of California, Irvine showed that chlorofluorocarbons (CFCs) can cause ozone depletion. Since that time, the so-called chlorofluorocarbon problem has become one of the main in the research on atmospheric pollution. Chlorofluorocarbons have been used for over 60 years as refrigerants in refrigerators and air conditioners, propellants for aerosol mixtures, foaming agents in fire extinguishers, cleaners for electronic devices, in dry cleaning of clothes, in the production of foam plastics. They were once considered ideal chemicals for practical use because they are very stable and inactive, which means they are not toxic. Paradoxically, it is the inertness of these compounds that makes them dangerous to atmospheric ozone. CFCs do not decay rapidly in the troposphere (the lower atmosphere, which extends from the earth's surface to an altitude of 10 km), as happens, for example, with most nitrogen oxides, and eventually penetrate into the stratosphere, the upper boundary of which is located at an altitude of about 50 km. When the CFC molecules rise to an altitude of about 25 km, where the ozone concentration is highest, they are exposed to intense ultraviolet radiation that does not penetrate to lower altitudes due to the shielding effect of ozone. Ultraviolet light destroys normally stable CFC molecules, which break down into highly reactive components, in particular atomic chlorine. Thus, CFCs carry chlorine from the earth's surface through the troposphere and the lower atmosphere, where less inert chlorine compounds are destroyed, into the stratosphere, to the layer with the highest ozone concentration. It is very important that chlorine acts like a catalyst in the destruction of ozone: during the chemical process, its amount does not decrease. Consequently, one chlorine atom can destroy up to 100,000 ozone molecules before being deactivated or returned to the troposphere. Now the emission of CFCs into the atmosphere is estimated at millions of tons, but it should be noted that even in a hypothetical case of a complete cessation of the production and use of CFCs, an immediate result will not be achieved: the effect of CFCs that have already entered the atmosphere will last for several decades. It is believed that the lifetimes in the atmosphere for the two most widely used CFCs, Freon-11 (CFCl 3) and Freon-12 (CF 2 Cl 2) are 75 and 100 years, respectively.

Nitrogen oxides are capable of destroying ozone, but they can also react with chlorine. For example:

2O 3 + Cl 2 → 2ClO + 2O 2

2ClO + NO → NO 2 + Cl 2

in the course of this reaction, the ozone content does not change. More important is the other reaction:

ClO + NO 2 → ClONO 2

the nitrosyl chloride formed in its course is the so-called chlorine reservoir. The chlorine it contains is inactive and cannot react with ozone. Eventually such a reservoir molecule can absorb a photon or react with some other molecule and release chlorine, but it can also leave the stratosphere. Calculations show that if nitrogen oxides were absent in the stratosphere, then ozone destruction would go much faster. Another important reservoir of chlorine is hydrogen chloride HCl, formed by the reaction of atomic chlorine and methane CH 4.

Under the pressure of these arguments, many countries have begun to take measures to reduce the production and use of CFCs. Since 1978, the US has banned the use of CFCs in aerosols. Unfortunately, the use of CFCs in other areas has not been restricted. In September 1987, 23 of the world's leading countries signed a convention in Montreal obliging them to reduce their consumption of CFCs. According to the agreement reached, developed countries must by 1999 reduce the consumption of CFCs to half of the 1986 level. A good substitute for CFCs, a propane-butane mixture, has already been found for use as a propellant in aerosols. In terms of physical parameters, it is practically not inferior to freons, but, unlike them, it is flammable. Nevertheless, such aerosols are already produced in many countries, including Russia. The situation is more complicated with refrigeration units - the second largest consumer of freons. The fact is that, due to the polarity, the CFC molecules have a high heat of vaporization, which is very important for the working fluid in refrigerators and air conditioners. The best known substitute for freons today is ammonia, but it is toxic and still inferior to CFCs in physical parameters. Quite good results were obtained for fully fluorinated hydrocarbons. In many countries, new substitutes are being developed and good practical results have already been achieved, but this problem has not yet been fully resolved.

The use of freons continues and is still far from even stabilizing the level of CFCs in the atmosphere. So, according to the Global Monitoring of Climate Change network, in background conditions - on the shores of the Pacific and Atlantic oceans and on islands, far from industrial and densely populated areas - the concentration of freons -11 and -12 is currently growing at a rate of 5-9% per year ... The content of photochemically active chlorine compounds in the stratosphere is currently 2-3 times higher than the level of the 1950s, before the rapid production of freons began.

At the same time, early forecasts predicting, for example, that while maintaining the current level of CFC emissions, by the middle of the XXI century. the ozone content in the stratosphere may fall by half, perhaps they were too pessemistic. First, the hole over Antarctica is largely a consequence of meteorological processes. The formation of ozone is possible only in the presence of ultraviolet radiation and does not occur during the polar night. In winter, a stable vortex forms over Antarctica, preventing the flow of ozone-rich air from mid-latitudes. Therefore, by spring, even a small amount of active chlorine can seriously damage the ozone layer. Such a vortex is practically absent over the Arctic, therefore, in the northern hemisphere, the drop in ozone concentration is much less. Many researchers believe that polar stratospheric clouds influence the ozone depletion process. These high-altitude clouds, which are much more often observed over Antarctica than over the Arctic, are formed in winter, when in the absence of sunlight and under conditions of meteorological isolation of Antarctica, the temperature in the stratosphere drops below -80 0 C. It can be assumed that nitrogen compounds condense, freeze and remain associated with cloudy particles and therefore deprived of the opportunity to react with chlorine. It is also possible that cloud particles can catalyze the breakdown of ozone and chlorine reservoirs. All this suggests that CFCs are capable of causing a noticeable decrease in ozone concentration only in the specific atmospheric conditions of Antarctica, and for a noticeable effect in mid-latitudes, the concentration of active chlorine must be much higher. Secondly, with the destruction of the ozone layer, hard ultraviolet light will begin to penetrate deeper into the atmosphere. But this means that the formation of ozone will continue, but only slightly lower, in the area with a high oxygen content. However, in this case, the ozone layer will be more exposed to atmospheric circulation.

Although the first gloomy estimates were revised, this by no means means that there is no problem. Rather, it became clear that there was no immediate grave danger. Even the most optimistic estimates predict, given the current level of CFC emissions into the atmosphere, serious biospheric disturbances in the second half of the 21st century, so it is still necessary to reduce the use of CFCs.

The possibilities of human impact on nature are constantly growing and have already reached a level where it is possible to cause irreparable damage to the biosphere. This is not the first time that a substance that has long been considered completely harmless turns out to be in fact extremely dangerous. Twenty years ago, hardly anyone could have imagined that an ordinary aerosol can could pose a serious threat to the planet as a whole. Unfortunately, it is far from always possible to predict in time how a particular compound will affect the biosphere. However, in the case of CFCs, there was such a possibility: all the chemical reactions describing the process of ozone destruction by CFCs are extremely simple and have been known for a long time. But even after the CFC problem was formulated in 1974, the only country that took any measures to reduce the production of CFCs was the United States and these measures were completely insufficient. It took a sufficiently serious demonstration of the danger of CFCs for serious action to be taken on a global scale. It should be noted that even after the discovery of the ozone hole, the ratification of the Montreal Convention was at one time under threat. Perhaps the problem of CFCs will teach with great attention and caution to all substances that enter the biosphere as a result of human activity.

Opening fees

Here are just a few episodes from this area. A sealed glass vessel containing an arsenic compound exploded in the hands of the German chemist Robert-Wilhelm Bunsen (1811-1899). The scientist was left without his right eye and was badly poisoned. Bunsen's hands were so coarse and scarred from working with chemicals that he preferred to hide them under the table in society. But in the laboratory he demonstrated their "invulnerability" by inserting his index finger into the flame of a gas "Bunsen burner" and holding it there for a few seconds until the smell of burning horn spread; while he calmly said: "Look, gentlemen, in this place the temperature of the flame is above a thousand degrees."

The French chemist Charles-Adolphe Würz (1817-1884), president of the Paris Academy of Sciences, had a violent explosion when heating a mixture of phosphorus trichloride PC1 3 and sodium Na in an open test tube. Shrapnel wounded his face and hands, got into his eyes. It was not possible to remove them immediately from the eyes. Gradually, however, they began to come out on their own. Only a few years later, the surgeons restored normal vision to Würz.

French physicist and chemist Pierre-Louis Dulong (1785-1838), a member of the Paris Academy of Sciences, paid dearly for the discovery of the explosive C1 3 N trichlorine nitride: he lost an eye and three fingers. Davy, studying the properties of this substance, also nearly lost his sight.

Russian academician Lehman died as a result of arsenic poisoning, which got into his lungs and esophagus when a retort exploded in the laboratory.

The German chemist Liebig nearly died when he inadvertently dropped the pestle, which he used to grind the crystals in a mortar, into a metal jar containing the highly explosive fulminate of mercury - "volatile mercury" Hg (CNO) 2. The explosion blew off the roof of the house, and Liebig himself was only thrown against the wall, and he escaped with bruises.

The Russian academician Lovitz was poisoned with chlorine in 1790. On this occasion, he wrote: "In addition to excruciating chest pain lasting for almost eight days, it also happened that when, through my negligence ... the gas was released into the air, I suddenly lost consciousness and fell to the ground."

Gay-Lussac and Thénard in one of their attempts to obtain potassium by heating a mixture of potassium hydroxide KOH and iron powder Fe according to the reaction:

6KOH + 2Fe = 6K + Fe 2 O 3 + 3H 2 O

nearly died due to the explosion of a laboratory facility. Gay Lussac spent almost a month and a half in bed recovering from his wounds. Another story happened to Tenar. In 1825, during a lecture on the chemistry of mercury, by mistake, instead of sugar water, he took a sip from a glass containing a solution of mercuric chloride (mercuric chloride HgCl 2) - a strong poison. He calmly put the glass back and calmly announced: “Lord, I have been poisoned. Raw eggs can help me, bring me them, please. " Frightened students rushed to neighboring shops and houses, and soon a pile of eggs rose in front of the professor. Thenar took in a raw egg, loose with water. This saved him. A raw egg is an excellent antidote for poisoning with mercury salts.

Russian academician Nikita Petrovich Sokolov (1748-1795) died of phosphorus and arsenic poisoning while studying the properties of their compounds.

Scheele's early death at the age of forty-four was apparently caused by poisoning with the hydrogen cyanide HCN and arsine AsH 3 he had received for the first time, the strong toxicity of which Scheele did not suspect.

Russian chemist Vera Evstafievna Bogdanovskaya (1867-1896) died at the age of twenty-nine while trying to react between white phosphorus P 4 and hydrocyanic acid HCN. The ampoule with these two substances exploded and injured her hand. Blood poisoning began, and four hours after the explosion, Bogdanovskaya died.

American chemist James Woodhouse (1770-1809) died at the age of thirty-nine from systematic carbon monoxide CO poisoning, unaware of the toxicity of this gas. He researched the reduction of iron ores with charcoal:

Fe 2 O 3 + 3C = 2Fe + 3CO

In the course of the study, carbon monoxide CO - "carbon monoxide" was released.

English chemist William Cruikshenk (1745-1810) in the last years of his life lost his mind due to the gradual poisoning with chlorine C1 2, carbon monoxide CO and carbon monoxide CC1 2 O (phosgene), the synthesis and study of the properties of which he was engaged.

German chemist Adolph von Bayer (1835-1917), Nobel laureate, synthesized methyldichloroarsine CH 3 AsCl 2 in his youth. Not knowing that this substance is a strong poison, he decided to smell it. Bayer immediately began to choke and soon passed out. He was rescued by Kekule by dragging Bayer out into the fresh air. Bayer was a trainee at Kekule.

Rare metals - the future of new technology

Figures and facts

Many rare metals, which for a long time almost did not find application, are now widely used in the world. They gave rise to whole new areas of modern industry, science and technology, such as solar energy, super-high-speed magnetic levitation transport, infrared optics, optoelectronics, lasers, and computers of the latest generations.

Using low-alloy steels containing only 0.03-0.07% niobium and 0.01-0.1% vanadium, it is possible to reduce the weight of structures by 30-40% in the construction of bridges, multi-storey buildings, gas and oil pipelines, geological drilling equipment and so on. In this case, the service life of the structures increases 2-3 times.

Magnets using superconducting niobium-based materials have made it possible to build hovercraft trains in Japan at speeds up to 577 km / h.

An ordinary American car uses 100 kg of HSLA steel with niobium, vanadium, rare earths, 25 parts made of copper-beryllium alloys, zirconium, yttrium. At the same time, the weight of a car in the USA (from 1980 to 1990) decreased 1.4 times. Since 1986, cars began to be equipped with neodymium magnets (37 g of neodymium per car)

Electric vehicles with lithium batteries, vehicles running on hydrogen fuel with lanthanum nitride and others are being intensively developed.

The American firm Westinghouse has developed high-temperature fuel cells based on zirconium and yttrium oxides, which increase the efficiency of thermal power plants from 35 to 60%.

Through the introduction of energy-efficient lighting devices and electronic equipment made using rare elements, the United States plans to save up to 50% of electricity from 420 billion kWh spent on lighting. In Japan and the USA, lamps with phosphors containing yttrium, europium, terbium, and cerium have been created. Lamps with a power of 27 W are successfully replacing 60-75 W incandescent lamps. Electricity consumption for lighting is reduced by 2-3 times.

The use of solar energy is impossible without gallium. NASA USA plans to equip space satellites with solar cells based on gallium arsenide.

The growth rate of consumption of rare metals in electronics is extremely high. In 1984, the global sales value of integrated circuits using gallium arsenide was $ 30 million, in 1990 it was already estimated at $ 1 billion.

The use of rare earth elements (rare earths) and the rare metal rhenium in oil cracking allowed the United States to drastically reduce the use of expensive platinum, while increasing the efficiency of the process and increasing the yield of high-octane gasoline by 15 percent.

In China, rare earths are successfully used in agriculture for fertilizing rice, wheat, corn, sugar cane, sugar beet, tobacco, tea, cotton, peanuts, fruits, flowers. The harvest of food crops increased by 5-10%, industrial crops - by more than 10%. The quality of wheat has improved due to the higher content of protein and lysine, the sugar content of fruits, sugar cane and beets has increased, the color of flowers has improved, the quality of tea and tobacco has improved.

In Kazakhstan, on the recommendation of Russian scientists, a new technique for the use of rare earths in agriculture, developed by FV Saykin, was applied. The experiments were carried out on large areas and received an excellent effect - an increase in the yield of cotton, wheat and other crops by 65%. Such a high efficiency was achieved, firstly, due to the fact that not a mixture of all rare earths was used at the same time, as was practiced in China, but only one neodymium (since some of the lanthanides do not increase the yield, but, on the contrary, reduce it). Secondly, they did not carry out, as is done in China, laborious spraying of agricultural plants during their flowering periods. Instead, they only soaked the grain before sowing in an aqueous solution containing neodymium. This operation is much simpler and cheaper.

Until recently, yttrium was used in technology extremely rarely, and its extraction was appropriate - it was calculated in kilograms. But it turned out that yttrium is able to dramatically increase the electrical conductivity of an aluminum cable and the strength of new ceramic structural materials. This promises a very large economic effect. Interest in yttrium and yttrium lanthanides - samarium, europium, and trebium - has grown significantly.

Scandium (its price at one time was an order of magnitude higher than the price of gold), thanks to the unique combination of a number of its properties, is now enjoying an extremely high interest in aviation, rocket and laser technology.

Hydrogen indicator ... of a person

It is known that the blood of a healthy person has a pH of 7.3-7.4. More precisely, blood plasma has a pH of about 7.36 - that is, the concentration of oxonium cations H 3 O + here is 4.4. 10 -8 mol / l. And the content of hydroxide ions OH in blood plasma is 2.3. 10 -7 mol / l, about 5.3 times more. Thus, the blood reaction is very weakly alkaline.

Changes in the concentration of oxonium cations in the blood are usually insignificant, firstly, due to the constant physiological adjustment of acid-base balance during the life of the body, and secondly, due to the presence of special "buffer systems" in the blood.

Buffer systems in chemistry are mixtures of weak acids with salts of the same acids (or weak bases with salts of the same bases). Examples of buffer systems are solutions of a mixture of acetic acid CH 3 COOH and sodium acetate CH 3 COONa or ammonia hydrate NH 3. H 2 O and ammonium chloride NH 4 Cl. Due to complex chemical equilibria, the blood buffer system maintains an approximately constant pH value even with the introduction of "excess" acid or alkali.

For blood plasma, the most important buffer system is carbonate (it consists of sodium bicarbonate NaHCO 3 and carbonic acid H 2 CO 3), as well as orthophosphate (hydrogen phosphate and sodium dihydrogen phosphate Na 2 HPO 4 and NaH 2 PO 4) and protein (hemoglobin) ...

The carbonate buffering system does a good job of regulating the acidity of the blood. If an increased amount of lactic acid, which is formed in the muscles from glucose during strenuous physical work, enters the blood, then it is neutralized. Carbonic acid is obtained, which is removed in the form of gaseous carbon dioxide, which is exhaled through the lungs.
With overstrain or illness, too many organic acids enter the bloodstream, the regulatory mechanisms fail, and the blood becomes excessively acidic. If the pH of the blood approaches 7.2, this is a signal of serious disturbances in the vital activity of the body, and at pH 7.1 and below, irreversible changes are fatal.

And human gastric juice contains acid and corresponds to a pH of 0.9 to 1.6. Due to the large amount of hydrochloric acid, gastric juice has a bactericidal effect.

Intestinal juice is almost neutral (pH 6.0 to 7.6). On the contrary, human saliva is always alkaline (pH 7.4 - 8.0).

And the acidity of "human juices" is regulated by urine, where the concentration of oxonium cations H 3 O + is very variable: the pH of this liquid can decrease to 5.0 and even to 4.7, or rise to 8.0, depending on the state of human metabolism.

The acidic environment suppresses the vital activity of harmful microorganisms and therefore serves as a kind of protection against infection. But the alkaline environment is a signal about the presence of inflammatory processes, which means about the disease.

Hydrogen technologies of the future in the automotive industry

The thesis "hydrogen is the fuel of the future" is being heard more and more often. Most of the major car manufacturers are doing experiments with fuel cells. Such experimental cars in large numbers flicker at exhibitions. But there are two companies that take a different approach to converting cars to hydrogen power.

Experts associate the "hydrogen future" of motor transport, first of all, with fuel cells. Everyone recognizes their appeal.

No moving parts, no explosions. Hydrogen and oxygen quietly and peacefully combine in a "box with a membrane" (this is how a fuel cell can be simplified) and give water vapor plus electricity.

Ford, General Motors, Toyota, Nissan and many other companies are vying to flaunt "fuel cell" concept cars and are about to "fill" everyone with hydrogen modifications of some of their conventional models.

Hydrogen filling stations have already appeared in several places in Germany, Japan, and the USA. In California, the first water electrolysis plants are being built using the current generated by solar panels. Similar experiments are being carried out all over the world.

It is believed that only hydrogen generated in an environmentally friendly way (wind, sun, water) will really provide us with a clean planet. Moreover, according to experts, "serial" hydrogen will not be more expensive than gasoline. The decomposition of water at high temperatures in the presence of a catalyst looks especially attractive here.

Doubtful ecological cleanliness of solar cell production; or the problem of recycling fuel cell car batteries (in fact, hybrids, since these are electric vehicles with a hydrogen power plant on board) - engineers prefer to speak second or third.

Meanwhile, there is another way of introducing hydrogen in vehicles - burning it in an internal combustion engine. This approach is shared by BMW and Mazda. Japanese and German engineers see this as their advantage.

The weight gain of the car is provided only by the hydrogen fuel system, while in the car on fuel cells the gain (fuel cells, fuel system, electric motors, current converters, powerful batteries) significantly exceeds the "savings" from removing the internal combustion engine and its mechanical transmission.

The loss in usable space is also less in a car with a hydrogen internal combustion engine (although the hydrogen tank in both cases eats up part of the trunk). This loss could be reduced to zero altogether if we made a car (with an internal combustion engine) that consumes only hydrogen. But this is where the main trump card of the Japanese and German "schismatics" appears.

This approach, as conceived by the automakers, will facilitate the gradual transition of vehicles only to hydrogen power. After all, a client will be able to buy such a car with a clear conscience when at least one hydrogen filling station appears in the region where he lives. And he won't have to worry about getting stuck at some distance from her with an empty hydrogen tank.

Meanwhile, serial production and mass sales of fuel cell vehicles will be severely constrained for a long time by the small number of such filling stations. Yes, and the cost of fuel cells is still high. In addition, converting conventional ICEs to hydrogen (with appropriate settings) not only makes them cleaner, but also increases thermal efficiency and improves operational flexibility.

The fact is that hydrogen has a much wider range of proportions of mixing it with air, in comparison with gasoline, at which the mixture can still be ignited. And hydrogen burns out more completely, even near the cylinder walls, where an unburned working mixture usually remains in gasoline engines.

So, it is decided - we "feed" hydrogen to the internal combustion engine. The physical properties of hydrogen are significantly different from those of gasoline. The Germans and Japanese had to break their brains over power systems. But the result was worth it.

The shown BMW and Mazda hydrogen cars combine the high performance with zero emissions familiar to conventional car owners. And most importantly, they are much better adapted to mass production than "ultra-innovative" fuel cell machines.

BMW and Mazda have made the knight's move by proposing a gradual transfer of vehicles to hydrogen. If you build cars that can run on both hydrogen and gasoline, say Japanese and German engineers, the hydrogen revolution will be velvet. This means more real.

The car builders of the two well-known companies have overcome all the difficulties associated with this hybridization. As with fuel cell cars, which are predicted to be dawn soon, the creators of cars with a hydrogen internal combustion engine first had to decide how to store hydrogen in the car.

The most promising option is metal hydrides - containers with special alloys that absorb hydrogen into their crystal lattice and release it when heated. This achieves the highest storage safety and the highest fuel packing density. But this is both the most troublesome and the longest in terms of mass implementation option.

Closer to mass production, fuel systems with tanks, in which hydrogen is stored in gaseous form under high pressure (300-350 atmospheres), or in liquid form, at a relatively low pressure, but low (253 degrees Celsius below zero) temperature. Accordingly, in the first case, we need a cylinder designed for high pressure, and in the second - the most powerful thermal insulation.

The first option is more dangerous, but hydrogen can be stored in such a tank for a long time. In the second case, the safety is much higher, but you cannot park a hydrogen car for a week or two. More precisely, you put it on, but the hydrogen, even though slowly, will heat up. The pressure will build up and the safety valve will start bleeding expensive fuel into the atmosphere.

Mazda has opted for a high-pressure tank option, while BMW has opted for liquid hydrogen.

The Germans understand all the shortcomings of their scheme, but now BMW is already experimenting with an unusual storage system, which it will put on its next hydrogen cars.

While the vehicle is in operation, liquid air is generated from the surrounding atmosphere and pumped into the gap between the walls of the hydrogen tank and the external insulation. In such a tank, hydrogen hardly heats up while the liquid air in the outer "jacket" evaporates. With such a device, they say at BMW, hydrogen in an idle car can be stored almost without loss for about 12 days.

The next important question is how fuel is supplied to the engine. But here you first need to go, in fact, to cars.

BMW has been operating a fleet of experienced hydrogen sevens for several years now. Yes, the Bavarians converted the flagship model to hydrogen. Note that BMW built the first hydrogen car in 1979, but only in the last few years has the company literally exploded with new hydrogen cars. Within the CleanEnergy program in 1999-2001, BMW built several dual-fuel (gasoline / hydrogen) "sevens".

Their 4.4-liter V-8 engine develops 184 horsepower on hydrogen. On this fuel (the capacity in the latest version of the car is 170 liters), limousines can travel 300 kilometers, and another 650 kilometers - on gasoline (a standard tank is left in the car).

The company also created a 12-cylinder dual-fuel engine and equipped the experimental MINI Cooper with a 4-cylinder 1.6-liter hydrogen engine.

The company first developed the injection of hydrogen gas into the intake pipes (in front of the valves). Then she experimented with direct injection of gaseous hydrogen (under high pressure) directly into the cylinder.

And later she announced that, in all likelihood, injecting liquid hydrogen into the area in front of the intake valves is the most promising option. But the final choice has not been made and research in this area will continue. Mazda has its own pride: it has adapted its famous rotary Wankel engines for hydrogen.

For the first time, a Japanese company built such a car in 1991, but it was a pure concept car from bumper to bumper.

But in January 2004, a bomb exploded. The Japanese showed a hydrogen (or rather, dual-fuel) version of their famous sports car RX-8. Its rotary engine with its own name, by the way, RENESIS, won the title of "Engine of the Year 2003", for the first time in history having outstripped classical piston rivals at this international competition.

And now RENESIS has been taught to "eat" hydrogen, while retaining gasoline power. At the same time, the Japanese emphasize the advantage of the Wankel engine with such a conversion.

There is a lot of free space in front of the intake ports in the rotary motor housing, where, unlike the tight cylinder head of a piston internal combustion engine, it is easy to place injectors. There are two of them for each of the two RENESIS sections.

In a Wankel engine, the suction, compression, stroke and exhaust chambers are separate (while in a conventional engine, they are the same cylinder).

Therefore, accidental premature ignition of hydrogen from the "oncoming fire" cannot occur here, and the injection nozzles always work in the favorable (in terms of durability) cold zone of the engine. On hydrogen, the Japanese Wankel develops 110 horsepower - almost half as much as on gasoline.

Generally speaking, based on weight, hydrogen is more energetically "rich" fuel than gasoline. But these are the fuel system settings chosen by Mazda engineers.

So BMW and Mazda have dealt a double blow to the fuel cell camp. Although the cost of the latter is constantly decreasing, and technologies are improving, it is possible that it is the serial ICEs on hydrogen that will open a new era on the roads of the planet.

Here is the forecast of the Bavarians.

In the next three years, hydrogen filling stations (at least one each) will be built in all Western European capitals, as well as on the largest trans-European highways.

Until 2010, the first dual-fuel cars will appear in stores. In 2015, there will be several thousand of them on the roads. In 2025, a quarter of the world's car fleet will be powered by hydrogen. The delicate Germans did not specify what proportion among hydrogen cars will be cars with internal combustion engines and cars on fuel cells.

Biblical miracles

As described in the Bible (Dan.V, 26, 28), during the feast of the Babylonian king Belshazzar, a hand appeared on the wall of the palace, writing words incomprehensible to those present: "Mene, Mene, Tekel, Uparsin." The Jewish prophet Daniel, having deciphered these words, predicted the death of Belshazzar, which soon happened.

If you dissolve white phosphorus in carbon disulfide CS 2 and draw a hand with the resulting concentrated solution on a marble wall, followed by words, you can observe a scene similar to the one recounted in the Bible. The solution of phosphorus in carbon disulfide is colorless, so the pattern is not visible at first. As CS 2 evaporates, white phosphorus is released in the form of tiny particles, which begin to glow and finally flare up - ignite spontaneously:

P 4 + 5O 2 = P 4 O 10;

when phosphorus is burned, the drawing and inscription disappear; the combustion product - tetraphosphorus decoxide P 4 O 10 - turns into a vaporous state and gives orthophosphoric acid with moisture in the air:

P 4 O 10 + 6H 2 O = 4H 3 PO 4,

which is observed in the form of a small cloud of bluish fog, gradually dissipating in the air.

You can add a small amount of white phosphorus to the solidifying wax or paraffin wax. If you make an inscription on the wall with a piece of frozen mixture, then at dusk and at night you can see it glowing. Wax and paraffin protect phosphorus from rapid oxidation and increase the duration of its luminescence.

Moses bush

Once, as the Bible tells (Ex. Sh, 1), the prophet Moses was tending sheep and saw that "a thorn bush burns with fire, but does not burn."

Among the sands of Sinai grows a bush diptam, which in those places is called "the bush of Moses." In 1960, Polish scientists grew this plant in a nature reserve, and on one hot summer day it really "caught fire" with a bluish-red flame, while remaining unharmed. Research has shown that the diptam shrub produces volatile essential oils. In calm, windless weather, the concentration of these volatile oils in the air around the bush increases sharply; when exposed to direct sunlight, they light up and burn quickly, releasing energy mainly in the form of light. And the bush itself remains intact and intact.

Many flammable substances of this kind are known. So, carbon disulfide CS 2 (under normal conditions it is a colorless, very volatile liquid) in the form of vapor is easily ignited by any heated object and burns with a light blue flame with such a low temperature that paper does not char in it.

Bitter spring

The Israelites, led by Moses, crossed the waterless desert of Sur. Thirsty, they hardly got to the town of Murr, but found that the water here is bitter and impossible to drink. "And they murmured against Moses ..." (Bible, Ex.XIV, 5-21). But God commanded the prophet to throw a tree growing nearby into the water. And - a miracle! - the water is drinkable!

In the vicinity of Merr, there is still a bitter