Which scientist was the first to obtain pure hydrogen. Who discovered the composition of water

After the work of J. Black, many chemists in various laboratories in England, Sweden, France, and Germany began to study gases. G. Cavendish achieved great success. All the experimental work of this scrupulous scientist was based on a quantitative research method. He widely used the weighing of substances and the measurement of gas volumes, guided by the law of conservation of mass. In the first work of G. Cavendnsh on the chemistry of gases (1766), methods of obtaining and properties are described.

"Combustible air" was known before (R. Boyle, N. Lemery). In 1745, M. V. Lomonosov, for example, noted that “when a base metal is dissolved, especially in acidic alcohols, combustible vapor escapes from the bottle opening, which is nothing more than phlogiston.” This is noteworthy in two respects: firstly, many years before the Cavendish, M. V. Lomonosov came to the conclusion that “combustible air” (i.e., hydrogen) is phlogiston; secondly, from the above quotation it follows that M. V. Lomonosov accepted the doctrine of phlogiston.

But no one before G. Cavendish tried to isolate "combustible air" and study its properties. In the chemical treatise Three Works Containing Experiments with Artificial Types of Air (1766), he showed that there are gases that differ from air, namely, on the one hand, "forest or bound air", which, as established by G. Cavendish turned out to be 1.57 times heavier than ordinary air, on the other hand, “combustible air” is hydrogen. G. Cavendish received it by the action of dilute acids and acids on various metals. The fact that under the action on (zinc, iron) the same gas (hydrogen) was released finally convinced G. Cavendish that all metals contain phlogiston, which is released during the transformation of metals into "earths". The English scientist took hydrogen for pure phlogiston, since the gas burns without leaving a residue, and metal oxides treated with this gas are reduced to the corresponding metals when heated.

Henry Cavendish

G. Cavendish, as a supporter of the theory of phlogiston, believed that it was not displaced by the metal from the acid, but was released as a result of the decomposition of the "complex" metal. He represented the reaction of obtaining "combustible air" from metals as follows:

What methods and instruments the "father of the chemistry of gaseous substances" used can be seen from the following. Leaving Leeds, J. Priestley, at the request of one of his acquaintances, left him a clay trough, which he used as a pneumatic bath in his experiments on the composition of air and which, J. Priestley ironically remarks, “was no different from the troughs in which laundresses wash clothes ". In 1772, J. Priestley replaced water with mercury in a pneumatic bath, which allowed him for the first time to obtain in pure form and study water-soluble gases: “hydrochloric acid air” () and “volatile alkaline air” - a colorless gas with a suffocating pungent odor. This was the one he got by heating ammonium chloride:

2NH 4 Cl + CaO \u003d 2NH 3 + CaCl 2 + H 2

“The gold placer discovered by Priestley was ... a mercury bath,” W. Ostwald wrote. “One step ahead on the technical side of things—water changes—is the key to most of Priestley’s discoveries.” J. Priestley observed that if an electric spark is passed through ammonia, then its volume increases sharply. In 1785, K.-L. Berthollet established that this was due to the decomposition of ammonia into nitrogen and hydrogen. J. Priestley observed that the interaction of two strongly smelling gases (HCl and NH 3) produces an odorless white powder (NH 4 Cl). In 1775, J. Priestley received, and c. 1796 - which he mistook for pure phlogiston.

History of the discovery of hydrogen

Many researchers have experimented with acids. It has been observed that when acids act on some metals, gas bubbles are released. The resulting gas was highly flammable and was called "combustible air".

The properties of this gas were studied in detail by the English scientist G. Cavendish in 1766. He placed metals in solutions of sulfuric and hydrochloric acids and in all cases received the same light gaseous substance, which was later called hydrogen.

An English scientist Henry Cavendish once took up a strange thing at first glance: he began to blow soap bubbles. But it wasn't fun. Before that, he noticed that when iron filings are doused with sulfuric acid, many bubbles of some kind of gas appear. What is this gas?

The scientist brought him out of the vessel through tubes. The gas was invisible. Does it have an odor? No. Then he filled them with soap bubbles. They went up easily! So gas is lighter than air! And if you set fire to the gas, it will light up with a bluish light. But the amazing thing is that when burned, water was obtained! Henry Cavendish named the new gas combustible air. After all, he, like ordinary air, was colorless and odorless. All this happened in the second half of the 18th century.

Later, the French chemist Antoine Laurent Lavoisier did the opposite: he obtained a "combustible gas" from water. He also gave the new gas another name - hydrogen, that is, "giving birth to water." Then scientists found that hydrogen is the lightest of all substances known to people, and its atoms are simpler than all others.

Hydrogen is very common. It is a part of all living beings, organisms, plants, rocks. It is everywhere: not only on Earth, but also on other planets and stars, on the Sun; especially a lot of it in outer space. The transformations that occur with hydrogen at gigantic pressure and temperatures of tens of millions of degrees enable the Sun to radiate heat and light. Hydrogen forms the most various compounds with carbon: oil and oil shale, gasoline and black asphalt. Such compounds are called hydrocarbons. Hydrogen is widely used in welding and cutting metals. If oxygen is added to carbon and hydrogen compounds, new compounds are obtained - carbohydrates, for example, substances that are not similar to each other, such as starch and sugar. And if you combine hydrogen with nitrogen, you will also get a gas - ammonia. It is necessary for the manufacture of fertilizers. Many of the advantages of hydrogen - environmentally friendly, energy-intensive, abundant in nature - have made it possible to use it as a rocket fuel. The same features of hydrogen make it promising as an aviation fuel.

Hydrogen is the lightest, simplest, and most abundant chemical element in the universe. It makes up about 75% of the total mass of elements in it. Hydrogen is found in large quantities in stars and gas giant planets. It plays a key role in the fusion reactions that take place in stars. Hydrogen is a gas with the molecular formula H2. At room temperature and normal pressure, hydrogen is a tasteless, colorless and odorless gas. Under pressure and in extreme cold, hydrogen turns into a liquid state. Hydrogen stored in this state takes up less space than in its "normal" gaseous form. Liquid hydrogen is also used as rocket fuel. At ultrahigh pressure, hydrogen solidifies and becomes metallic hydrogen. Research is being carried out in this direction. Hydrogen is used as an alternative fuel for transport. The chemical energy of hydrogen is released when it is burned in a manner similar to that used in traditional internal combustion engines. On its basis, fuel cells are also created, in which the process of forming water and electricity is involved in the chemical reaction of hydrogen with oxygen. It is potentially dangerous to humans because it can ignite on contact with air. In addition, this gas is not suitable for breathing.

Hydrogen has been used in aeronautics since 1852, ever since the first hydrogen-powered airship was created by Henry Giffard. Hydrogen airships were later called "zeppelins". Their use was discontinued after the crash of the Hindenburg airship in 1937. The accident was caused by a fire.

Hydrogen is also widely used in the petroleum and chemical industries, and is also often used for various physical and engineering tasks: for example, in welding and as a coolant. Molecular formula of hydrogen peroxide H2O2. This substance is often used to bleach hair and as a cleaning agent. In the form of a medical solution, it is also used to treat wounds.

Since hydrogen is 14 times lighter than air, if you fill balloons with it, they will move away from the Earth at a speed of 85 km per hour, which is twice the speed of balloons filled with helium, and six times the speed of balloons filled with natural gas. .

chemical hydrogen peroxide gas

Bibliography

1. http://www.5.km.ru/
2. http://hi-news.ru/science/ximiya-14-faktov-o-vodorode.html.

03.10.2015

We all know that the most abundant element in our universe is hydrogen. It is the main constituent of stars. Of all atoms, its share is 88.6%. The processes taking place on Earth are simply not possible without the action of hydrogen. It, unlike many other elements, is in the form of various compounds. Its mass fraction of a simple substance in the air is negligible.

Name of the element in Latin Hydrogenium consists of two Greek words, translated meaning water and give birth- that is, giving birth to water. So called it Lavoisier, but in the XVII century. Academician V.M. Severgin decided to commemorate this element as a "water-forming substance". The name hydrogen in Russia was proposed in 1824 by the chemist Solovyov, by similarity as "oxygen". In the chemical literature of Russia until the 19th century, one can see such names of the element - combustible gas, combustible air or whirlpool, hydrogen gas, created creature.

For a long time, experiments on the study and discovery of many gases were ignored, since the experimenters simply did not notice these invisible substances. Only with time was the conviction consolidated that gas is the same material, without the study of which it is not possible to fully understand the chemical basis of the world. The discovery of hydrogen occurred in the very development of chemistry as a science. In the XI-XII centuries, gas was released during the interaction of the metal with acids. Paracelsus, Lomonosov, Boyle and other scientists and inventors observed its burning. But the main part of them in those years was committed to the theory of phlogiston.

Lomonosov, in 1745, when writing his dissertation, described the production of gas by the action of acids on metals. The phlogiston hypothesis was also put forward by the chemist Henry Cavendish, who studied the properties of hydrogen in more detail, giving it the name "combustible air". Only by the end of the 12th century, using modern laboratory instruments, Lavoisier, together with Meunier, carried out water synthesis. They made an analysis of water vapor, which was decomposed using hot iron. Thanks to this experience, it became clear that hydrogen is present in the composition of water; in addition, it can be obtained from it.

The turn of the XIII-XIX centuries was marked by one discovery - it was discovered that the hydrogen atom is quite light, along with other elements, it was customary to consider the weight of this element as a unit of comparison. Its atomic mass was assigned a value of 1. When Lavoisier presented the table of simple substances, he attributed hydrogen there to 5 simple bodies (hydrogen, oxygen, nitrogen, light, heat). It was generally accepted that these substances were from 3 natural kingdoms and were considered elements of bodies.

In addition to the discovery of the element itself, scientists later discovered its isotopes. It happened in more modern times, in 1931. A group of scientists was studying the residue, which was formed during the long evaporation of hydrogen in a liquid state. During the experiment, hydrogen was discovered, the atomic number of which was 2. It was given the name Deuterium (second). After only 4 years, during long-term electrolysis of water, an even heavier isotope was discovered, which was called Tritium (third).

is a gas, the importance of which in the existence of life on the planet began billions of years ago. According to modern guesses, hydrogen (H2) appeared about 14 billion years ago. It has no color or smell, and is the lightest element in the Periodic Table of Chemical Elements, with an atomic mass of 1.00794. Hydrogen has a hexagonal crystal structure and at 0° Celsius its density is 0.09099 g/l.

It can be considered an "aristocratic" gas, since it was discovered in 1766 by the British philosopher, physicist and chemist of noble origin Henry Cavendish, and it received its name in 1783 thanks to the French physicist, also of noble origin, Antoine Lavoisier. Lord Cavendish preferred to call his discovery "combustible air". The fantastically wealthy Lord Cavedish was so shy and withdrawn that one of his estates even had a separate staircase to the entrance due to the fact that he could not communicate with servants, especially females, with whom he was especially shy and communicated only through notes. According to modern assumptions, Henry Cavendish suffered from Asperger's syndrome.

As for Antoine Lavoisier, his end was sad: after all the important scientific works, he was deprived of his head by the French peasants with the help of a guillotine during the French Revolution. A few weeks after the incident, they admitted their mistake and apologized to Antoine Lavoisier's family, and later even erected a statue in his honor. But due to lack of funds, the head of another gentleman was attached to the statue of Lavoisier. It seems quite ironic, doesn't it?

The adaptability is simply amazing. Hydrogen is capable of producing electricity, which is why it is used in fuel cells and, being the cleanest option, in internal combustion engines.

Hydrogen originated as a result of the big bang and, since then, has been operating in various spheres on Earth. Over the past three and a half billion years, it has been actively involved in the production of water, as well as the birth and maintenance of cellular life.

Today, hydrogen (H2) is under intense scrutiny in medical research. Hundreds of scientific studies have proven the therapeutic potential of hydrogen-enriched water for more than 140 different disease models.

Here is a brief overview of some of the therapeutic possibilities of hydrogen and hydrogen water:

reduces the surface tension of cells, allowing them to better absorb nutrients.
This is the smallest one with high bioavailability.
Hydrogen eliminates only the most destructive ones, turning them into safe water without any toxic waste.
enhances the action of antioxidants such as glutathione and superoxide dismutase.
helps in the implementation of proper hydration of cells.
Hydrogen water reduces lactic acid and thus relieves muscle pain during and after exercise.
promotes the production of ATP in mitochondria.
Hydrogen water enhances the function of mitochondria in the brain, thereby improving brain activity. It also maintains the balance of sugar and cholesterol.
Hydrogen water has an anti-inflammatory effect and protects against the harmful effects of radiation. Therefore, the use

Hydrogen in nature

Is there a lot of hydrogen in nature? Watching where. In space, hydrogen is the main element. It accounts for about half the mass of the Sun and most other stars. It is contained in gaseous nebulae, in interstellar gas, and is part of the stars. In the interior of stars, the nuclei of hydrogen atoms are converted into the nuclei of helium atoms. This process proceeds with the release of energy; for many stars, including the Sun, it serves as the main source of energy.

For example, the closest star to us in the Galaxy, which we know under the name "Sun", is 70% of its mass hydrogen. There are several tens of thousands of times more hydrogen atoms in the universe than all the atoms of all metals combined.

Hydrogen is widely distributed in nature, its content in the earth's crust (lithosphere and hydrosphere) is 1% by weight. Hydrogen is part of the most common substance on Earth - water (11.19% hydrogen by mass), in the compounds that make up coal, oil, natural gases, clay, as well as animal and plant organisms (that is, in the composition of proteins, nucleic acids , fats, carbohydrates, etc.). Hydrogen is extremely rare in the free state; it is found in small amounts in volcanic and other natural gases. Negligible amounts of free Hydrogen (0.0001% by number of atoms) are present in the atmosphere.

Task number 1. Fill in the table "Finding hydrogen in nature."

In a free state	In bound state
	Hydrosphere -
	Lithosphere -
	Biosphere -

Discovery of hydrogen.

Hydrogen was discovered in the first half of the 16th century by the German physician and naturalist Paracelsus. In the works of chemists of the XVI-XVIII centuries. "combustible gas" or "flammable air" was mentioned, which, in combination with the usual one, gave explosive mixtures. It was obtained by acting on some metals (iron, zinc, tin) with dilute solutions of acids - sulfuric and hydrochloric.

The first scientist to describe the properties of this gas was the English scientist Henry Cavendish. He determined its density and studied combustion in air, however, adherence to the theory of phlogiston prevented the researcher from understanding the essence of the ongoing processes.

In 1779, Antoine Lavoisier obtained hydrogen by decomposing water by passing its vapors through a red-hot iron tube. Lavoisier also proved that when "combustible air" interacts with oxygen, water is formed, and the gases react in a volume ratio of 2: 1. This allowed the scientist to determine the composition of water - H 2 O. The name of the element is Hydrogenium- Lavoisier and his colleagues formed from the Greek words " hydro" - water and " gennio"I am giving birth. The Russian name "hydrogen" was proposed by the chemist M.F. Solovyov in 1824 - by analogy with Lomonosov's "oxygen".

Task number 2. Write the reaction for obtaining hydrogen from zinc and hydrochloric acid in molecular and ionic form, make an OVR.