Hydrogen chemicals. Hydrogen

Building and physical properties of hydrogenHydrogen - Dihomanny GAZ H2. It has no color, no smell. This is the easiest gas. Due to this property, it was used in aerostats, airships and similar devices, but its explosion hazard in the mixture with air interferes with widespread use of hydrogen.

Hydrogen molecules are non-polar and very small, so there is little interaction between them. In this regard, it has very low melting points (-259 ° C) and boiling (-253 ° C). Hydrogen is practically insoluble in water.

Hydrogen has 3 isotope: normal 1H, deuterium 2H or D, and radioactive tritium 3N or T. Heavy isotopes of hydrogen are unique in that heavier than the usual hydrogen in 2 or even 3 times! That is why the replacement of ordinary hydrogen on deuterium or tritium is noticeably affected by the properties of the substance (so, the boiling point of conventional hydrogen H2 and the deuterium D2 differ by 3.2 degrees). The interaction of hydrogen with simple substances Hydrogen - non-metal of the middle electrical negativity. Therefore, it is also inherent in oxidative, and rehabilitation properties.

The oxidative properties of hydrogen are manifested in reactions with typical metals - elements of the main subgroups of the I-II group of the Mendeleev table. The most active metals (alkaline and alkaline earth) when heating with hydrogen give hydrides - solid saline substances containing hydride ion-ion in the crystal lattice. 2NA + H2 \u003d 2NA ; Ca + H2 \u003d San2 The reducing properties of hydrogen are manifested in reactions with more typical non-metals than hydrogen: 1) Interaction with halogens H2 + F2 \u003d 2HF

Similarly, interaction with analogs of fluorine - chlorine, bromine, iodine. As the halogen activity decreases, the intensity of the reaction is reduced. The reaction with fluorine occurs under normal conditions with an explosion, for reaction with chlorine requires lighting or heating, and the reaction with iodine proceeds only with strong heating and reversible. 2) interaction with oxygen2N2 + O2 \u003d 2N2O The reaction proceeds with high heat release, sometimes with an explosion. 3) interaction with gray H2 + S \u003d H2S sulfur - much less active nonmetall than oxygen, and the interaction with hydrogen proceeds calmly. 4) interaction with nitrogen 3H2 + N2↔ 2NH3 Reaction is reversible, proceeds to a noticeable extent in the presence of a catalyst, when heated and under pressure. The product is called ammonia. 5) Cooperation with carbon C + 2N2↔ CH4 reaction proceeds in an electric arc or at very high temperatures. Other hydrocarbons are formed as by-products. 3. The interaction of hydrogen with complex substances Hydrogen shows reducing properties and in reactions with complex substances: 1) restoration of metal oxides facing the electrochemical row of stresses to the right of aluminum, as well as non-metallic oxides: Fe2O3 + 2H2 2fe + 3H2O ; Cuo + H2 Cu + H2Ocarrow is used as a reducing agent for extracting metals from oxide ores. Reactions go when heated.2) attach to organic unforeseen substances; C2H4 + H2 (T; P) → C2H6 reactions are processed in the presence of a catalyst and under pressure. We will not concern other hydrogen reactions yet. 4. Obtaining hydrogenIn industry, hydrogen is obtained by processing hydrocarbon raw materials - natural and associated gas, coke, etc. Laboratory methods for producing hydrogen:

1) the interaction of metals in the electrochemical row of metal voltages to the left of hydrogen, with acids. Li K Ba Sr Ca Na Mg Al Mn Zn Cr Fe CD CO Ni Sn Pb (H2) Cu Hg AG PT Mg + 2HCl \u003d MgCl2 + H22) The interaction of metals in the electrochemical row of metal voltages to the left of magnesium, with cold water. It also forms alkali.

2NA + 2H2O \u003d 2NAOH + H2 Metal, which is in the electrochemical row of metal voltages to the left of manganese, is able to exhibit hydrogen from water under certain conditions (magnesium - from hot water, aluminum - under the condition that the oxide film is removed from the surface).

Mg + 2H2O MG (OH) 2 + H2

Metal, located in the electrochemical row of stresses of metals to the left cobalt, is able to exhibit hydrogen from water vapor. This also forms oxide.

3Fe + 4H2OPar Fe3O4 + 4H23) Metal reaction, hydroxides of amphoterns, with alkalis solutions.

Metals, hydroxides of which are amphoterns, squeeze hydrogen from alkalis solutions. You need to know 2 such metal - aluminum and zinc:

2AL + 2NAOH + 6H2O \u003d 2NA + + 3H2

Zn + 2KOH + 2H2O \u003d K2 + H2

At the same time, complex salts are formed - hydroxyaluminates and hydroxotocytes.

All methods listed so far are based on the same process - metal oxidation at the hydrogen atom in the degree of oxidation +1:

M0 + nn + \u003d mn + + n / 2 h2

4) The interaction of hydrides of active metal metals:

San2 + 2N2O \u003d sa (it) 2 + 2N2

This process is based on the interaction of hydrogen into the degree of oxidation -1 with hydrogen into the degree of oxidation +1:

5) Electrolysis of aqueous alkali solutions, acids, some salts:

2N2O 2N2 + O2

5. Hydrogen compoundsIn this table, the cells of the elements forming with hydrogen-hydrides are isolated on the left shadow. These substances are in their composition hydride ion N-. They are solid colorless saline substances and react with water with hydrogen release.

Elements of the main subgroups of IV-VII groups form with hydrogen compounds of the molecular structure. Sometimes they are also called hydrides, but it is incorrect. In their composition there is no hydride ion, they consist of molecules. As a rule, the simplest hydrogen compounds of these elements are colorless gases. Exceptions - water, which is liquid, and fluoride fluoride, which at room temperature gaseous, but under normal conditions - liquid.

Dark cells marked elements that form with hydrogen compounds showing acid properties.

Dark cells with a cross are elements forming with hydrogen compounds that show the basic properties.

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29). The overall characteristics of the properties of the elements of the main subgroup of 7g. Chlorine. Properties of Laura. Hydrochloric acid.In the subgroup of halogens, the fluorine, chlorine, bromine, iodine and astat (Astat is a radioactive element, is studied little). These are p-elements of the VII group of the periodic system D.I. Imendeev. At the external energy level, their atoms have 7 NS2NP5 electrons. This explains the commonality of their properties.

They easily join one electron, showing the degree of oxidation -1. Such a degree of oxidation of halogens have in compounds with hydrogen and metals.

However, halogen atoms, except fluoride, can also show positive degrees of oxidation: +1, +3, +5, +7. Possible values \u200b\u200bof oxidation are explained by the electron structure, which at the fluorine atoms can be represented

Being the most electronegative element, the fluorine can only take one electron by 2p.

The electronic structure of the chlorine atom is expressed by the chlorine atom scheme one unpaired electron on a 3p pioneer and a conventional (unexcited) state of chlorine monovalent. But since Chlorine is in the third period, he has five more orbitals 3D-sublevels, in which 10 electrons can accommodate.

Fluorine does not have free orbital, and therefore, with chemical reactions, paired electron in the atom does not separate. Therefore, during the examination of halogen, it is always necessary to take into account the features of fluorine and compounds.

The aqueous solutions of halogen hydrogen compounds are acids: HF - fluoride hydrogen (plumbing), HCl - chloride (hydrogen), HBR - brominery, ni - iodium.

Chlorine (lat.chlorum), cl, chemical element VII group of periodic Mendeleev system, atomic number 17, atomic weight 35,453; refers to the family of halogens. Under normal conditions (0 ° C, 0.1 mn / m2, or 1 kgf / cm2), yellow-green gas with a sharp annoying smell. Natural chlorine consists of two stable isotopes: 35SL (75.77%) and 37CL (24.23%).

Chemical properties chlorine. External electronic configuration of the CL 3S2ZP5 atom. In accordance with this, chlorine in the compounds exhibits the degree of oxidation -1, + 1, +3, +4, +5, +6 and +7. The covalent radius of the atom of 0.99Å, the ion radius of CL- 1.82Å, the affinity of the chlorine atom to the electron is 3.65 eV, the ionization energy is 12.97 eV.

Chemically chlorine is very active, directly connects with almost all metals (with some only in the presence of moisture or when heated) and with non-metals (except carbon, nitrogen, oxygen, inert gases), forming appropriate chlorides, react with many compounds, replaces hydrogen In limit hydrocarbons and joins unsaturated compounds. Chlorine displaces bromine and iodine from their compounds with hydrogen and metals; From chlorine compounds with these elements, it is supplanted with fluorine. Alkaline metals in the presence of moisture traces interact with chlorine with ignition, most of the metals react with dry chlorine only when the phosphorus is heated, the phosphorus is flammable in the chlorine atmosphere, forming PCl3, and with further chlorination - RSL5; The chlorine sulfur when heated gives S2Cl2, SCL2 and other SNCLM. Arsenic, antimony, bismuth, strontium, Tellur interact vigorously with chlorine. A mixture of chlorine with hydrogen is lit with a colorless or yellow-green flame with the formation of hydrogen chloride (this is a chain reaction). With oxygen chlorine forms oxides: CL2O, CLO2, CL2O6, CL2O7, CL2O8, as well as hypochlorites (chlorothic acid salts), chlorite, chlorates and perchlorates. All chlorine oxygen compounds form explosive mixtures with easily oxidizing substances. Chlorine in water is hydrolyzed, forming a chloronous and hydrochloric acid: CL2 + H2O \u003d NCLO + HCl. When chloroing aqueous solutions, hypochlorites and chlorides are formed by alkali: 2NAOH + CL2 \u003d NACLO + NaCl + H2O, and when heated is chlorates. Calcium hydroxide chlorination is obtained by chlorine lime. In the interaction of ammonia with chlorine, three chloride nitrogen is formed. In chlorination of organic compounds, chlorine either replaces hydrogen, or is attached to multiple bonds, forming various chlorine-containing organic compounds. Chlorine forms interground compounds with other halogens. Fluorides CLF, CLF3, CLF3 are very reactive; For example, in the CLF3 atmosphere, glass wool is self-proposal. Known chlorine compounds with oxygen and fluorine - chlorine oxyfluorides: CLO3F, CLO2F3, CLOF, CLOF3 and fluorine perchlorate FCLO4. Hydrochloric acid (hydrogen chloride, hydrogen chloride, hydrogen chloride) - HCl, solution of hydrogen chloride in water; Strong monoise acid. Colorless (technical hydrochloric acid is yellowish due to impurities Fe, CL2, etc.), "smoking" in the air, caustic liquid. The maximum concentration at 20 ° C is 38% by weight. Salt hydrochloric acid are called chlorides.

Interaction with strong oxidizing agents (potassium permanganate, manganese dioxide) with the release of gaseous chlorine:

Interaction with ammonia with the formation of thick white smoke consisting of the smallest crystals of ammonium chloride:

The high-quality reaction to hydrochloric acid and its salt is its interaction with silver nitrate, in which the forms of silver chloride precipitate is insoluble in nitric acid:

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Hydrogen is gas, it is he in the first place in the periodic system. The name of this widespread element in the nature of the Latin means "generating water". So what physical and chemical properties of hydrogen are known to us?

Hydrogen: General Information

Under normal conditions, hydrogen has no taste, no smell, nor colors.

Fig. 1. Formula of hydrogen.

Since the atom has one energy electron level, on which there may be a maximum of two electrons, then for a stable state, an atom can be accepted as one electron (the degree of oxidation -1), so to give one electron (the degree of oxidation +1), showing constant valence I . That is why the hydrogen element symbol is placed not only in the IA group (the main subgroup I group) together with alkaline metals, but also in the VIIIA group (the main subgroup of the group VII) together with halogens. Halogen atoms are also lacking one electron before filling out the external level, and they, like hydrogen, are non-metals. Hydrogen shows a positive degree of oxidation in compounds, where it is associated with more electronegative elements - non-metals, and the negative degree of oxidation is in compounds with metals.

Fig. 2. The location of hydrogen in the periodic system.

At hydrogen, there are three isotopes, each of which has its own name: participants, deuterium, tritium. The number of latter on earth is negligible.

Chemical properties of hydrogen

In a simple substance H 2, the connection between the atoms is durable (bond energy 436 kJ / mol), therefore the activity of molecular hydrogen is small. Under normal conditions, it interacts only with very active metals, and the only non-metallol with which hydrogen enters into the reaction is fluorine:

F 2 + H 2 \u003d 2HF (fluoride hydrogen)

With other simple (metals and non-metals) and complex (oxides, organic uncertain compounds), hydrogen substances react to either when irradiated and increasing the temperature or in the presence of a catalyst.

Hydrogen burns in oxygen with highlighting a significant amount of heat:

2H 2 + O 2 \u003d 2H 2 O

A mixture of hydrogen with oxygen (2 hydrogen volumes and 1 oxygen volume) when the ignition is strongly exploded and therefore wears the name of the rattling gas. When working with hydrogen, the safety regulations should follow.

Fig. 3. REDUCH GAS.

In the presence of catalysts, gas can react with nitrogen:

3H 2 + N 2 \u003d 2NH 3

- in this reaction at elevated temperatures and pressure in the industry, ammonia is obtained.

In high temperature conditions, hydrogen is capable of reacting with gray, selenium, tellurium. And when interacting with alkaline and alkaline earth metals, hydrides are formulated: 4.3. Total ratings received: 186.

Getting Started with the consideration of the chemical and physical properties of hydrogen, it should be noted that in the usual state, this chemical element is in a gaseous form. Colorless hydrogen gas has no smell, he is tasteless. For the first time, this chemical element was named hydrogen after a scientist A. Lavoisier conducted experiments with water, based on the results of which, world science learned that water is a multicomponent liquid, which includes hydrogen. The event was happening in 1787, but long before this date hydrogen was known as a scientist called "combustible gas".

Hydrogen in nature

According to scientists, hydrogen is contained in the earth's crust and in water (approximately 11.2% in the total volume of water). This gas is part of many minerals that humanity over the centuries extracts from the bowels of the earth. Partially properties of hydrogen are characteristic of oil, natural gases and clay, for animal organisms and plants. But in its pure form, that is, not connected to other chemical elements of the Mendeleev table, this gas is extremely rare in nature. This gas can go to the surface of the Earth when eruption of volcanoes. Free hydrogen in insignificant quantities is present in the atmosphere.

Chemical properties of hydrogen

Since the chemical properties of hydrogen are inseparable, this chemical element refers to the I group of the Mendeleev system and to the VII system group. As a representative of the first group, hydrogen is, in fact, an alkaline metal, which has an oxidation degree of +1 in most of the compounds in which it enters. The same valence is characteristic of sodium and other alkali metals. In view of such chemical properties, hydrogen is considered as an element similar to these metals.

If we are talking about metal hydrides, the hydrogen ion has a negative valence - its degree of oxidation is -1. Na + H- is based on the same scheme as Na + Cl- chloride. This fact is the reason for the hydrogen to the VII group of the Mendeleev system. Hydrogen, being able to a molecule, provided that it resides in a normal medium, is sedimed, and can be connected exclusively with non-metals, more active for it. Such metals include fluorine, if there is light, hydrogen is connected to chlorine. If hydrogen is heated, then it becomes more active, entering into reactions with many elements of the periodic Mendeleev system.

Atomic hydrogen exhibits more active chemical properties than molecular. Oxygen molecules C form water - H2 + 1 / 2O2 \u003d H2O. When hydrogen interacts with halogens, the H2 + CL2 \u003d 2NCL halogen hydrogen are formed, and in this reaction, hydrogen enters in the absence of light and at sufficiently large negative temperatures - up to - 252 ° C. The chemical properties of hydrogen allow it to be used to restore many metals, since reacting, hydrogen absorbs oxygen oxygen, for example, Cuo + H2 \u003d Cu + H2O. Hydrogen is involved in the formation of ammonia, interacting with nitrogen in the reaction of ZN2 + N2 \u003d 2NN3, but provided that the catalyst will be used, and the temperature and pressure are increased.

The energetic reaction occurs when hydrogen interacts with sulfur in the reaction H2 + S \u003d H2S, the result of hydrogen sulfide. Slightly less active in the interaction of hydrogen with tellurium and selenium. If there is no catalyst, it reacts with pure carbon, hydrogen only under the condition that high temperatures will be created. 2N2 + C (amorphous) \u003d CH4 (methane). In the process of hydrogen activity with some alkaline and other metals, hydrides are obtained, for example, H2 + 2Li \u003d 2LIH.

Physical properties of hydrogen

Hydrogen is a very light chemical. At least scientists argue that at the moment there is no lighter than the substance than hydrogen. Its mass is 14.4 times easier for air, the density is 0.0899 g / l at 0 ° C. At temperatures in -259.1 ° C, hydrogen is capable of melting - this is a very critical temperature that is not characteristic of transforming most chemical compounds from one state to another. Only such an element as helium exceeds the physical properties of hydrogen in this regard. The liquefaction of hydrogen is difficult, since its critical temperature is equal to (-240 ° C). Hydrogen is the largest gas of all known to humanity. All the properties described above are the most significant physical properties of hydrogen, which are used by a person for specific purposes. Also these properties are the most relevant for modern science.

History of discovery of hydrogen

If it is the most common chemical element on Earth, the hydrogen is the most common element throughout the universe. Our (and other stars) about half consists of hydrogen, and as for the interstellar gas, it consists of 90% of hydrogen atoms. Considerable place this chemical element occupies on Earth, because with oxygen it is part of the water, and its very name "hydrogen" comes from two ancient Greek words: "Water" and "Gignify". In addition to the water, hydrogen is present in most organic substances and cells, without it, as without oxygen, life itself would be unthinkable.

History of discovery of hydrogen

The first among scientists, hydrogen, the Great Alchemist and the Middle Ages Theophrast Paracels were noticed. In their alchemical experiments, in the hope of finding the "philosopher's stone" mixing with the acids of Paracels received a certain unknown to be combustible gas. True, it was not possible to separate this gas from the air.

Only after a century after Paracella, the French chemist Lemerie was able to separate hydrogen from the air and prove its flamminess. True Lecheri did not understand that the gas obtained by them is pure hydrogen. In parallel, the Russian scientist of Lomonosov was also engaged in such chemical experiences, but the real breakthrough in the hydrogen study was made by the British chemist Henry Cavendish, who is rightfully considered to be a hydrogen discoverer.

In 1766, Cavendish managed to get pure hydrogen, which he called "flammable air". After 20 years, the talented French chemist Antoine Lavoisier could synthesize the water and allocate this most "combustible air" from it - hydrogen. And by the way, the Lavoisier suggested its name hydrogen - "Hydrogenium", he is "hydrogen".

Antoine Lavauzier with his wife, who helped him carry out chemical experiments, including the synthesis of hydrogen.

The basis of the location of the chemical elements in the periodic system of Mendeleev is their atomic weight, calculated relative to the atomic weight of hydrogen. That is, in other words, hydrogen and its atomic weight is the cornerstone of the Mendeleev table, the point of support, on the basis of which the great chemist created its system. Therefore, it is not surprising that in the Table of Mendeleev, hydrogen occupies an honorable place.

In addition, hydrogen has such characteristics:

The atomic mass of hydrogen is 1.00795.
In hydrogen, there are three isotopes, each of which has individual properties.
Hydrogen is a lightweight element having a small density.
Hydrogen has restorative and oxidative properties.
When entering into with metals, hydrogen takes their electron and becomes the oxidizing agent. Such compounds are called hydrates.

Hydrogen is gas, its molecule consists of two atoms.

So schematically looks hydrogen molecule.

Molecular hydrogen, formed from such ductomic molecules, explodes with a brought up burning match. The hydrogen molecule during the explosion disintegrates atoms, which are converted into the helium nucleus. It is in this way that happened in the sun and other stars - due to the constant breakdown of hydrogen molecules, our luminaire burns and heats us with its warmth.

Physical properties of hydrogen

At hydrogen in the presence of the following physical properties:

The boiling point of hydrogen is 252.76 ° C;
And at a temperature of 259.14 ° C, it is already starting to melt.
In water, hydrogen dissolves weakly.
Pure hydrogen is a very dangerous explosive and fuel.
Hydrogen is lighter than air 14.5 times.

Chemical properties of hydrogen

Since hydrogen can be used in different situations and the oxidizing agent and the reducing agent for reactions and synthesis.

The oxidative properties of hydrogen interact with active (usually alkaline and alkaline earth) metals, the result of these interactions is the formation of hydrides - silk-like compounds. However, hydrides are formed in hydrogen reactions with low-active metals.

The reducing properties of hydrogen have the ability to restore metals to simple substances from their oxides, this is called hydrogen heroes in industry.

How to get hydrogen?

Among the industrial means of obtaining hydrogen can be allocated:

coal gasification
steam conversion of methane,
electrolysis.

In the laboratory, hydrogen can be obtained:

with hydrolysis of metal hydrides,
when reactions with water alkali and alkaline earth metals,
in the interaction of diluted acids with active metals.

The use of hydrogen

Since hydrogen is 14 times lighter than air, then in the old days they started the balloons and airships. But after the series of disasters that occurred with the airships, designers had to look for hydrogen to replace (reminding, pure hydrogen - an explosive substance, and the slightest spark was enough to have an explosion).

The explosion of the airship of Hindenburg in 1937, the cause of the explosion just became the ignition of hydrogen (due to short circuit), which flew this huge airship.

Therefore, it began to use helium instead of hydrogen for such aircraft instead of hydrogen, which is also lighter than air, the receipt of helium is more laborious, but it is not so explosive as hydrogen.

Also, with hydrogen, various types of fuel are purified, especially on the basis of oil and petroleum products.

Hydrogen, video

And at the end of the educational video on our article.

Designation - H (Hydrogen);
Latin name - Hydrogenium;
Period - I;
Group - 1 (Ia);
Atomic mass - 1,00794;
Atomic number - 1;
Radius of atom \u003d 53 PM;
Covalent radius \u003d 32 PM;
Electron distribution - 1s 1;
t melting \u003d -259,14 ° C;
t boiling \u003d -252,87 ° C;
Electricity (by Paulonga / by Alpreda and Rokhov) \u003d 2.02 / -;
The degree of oxidation: +1; 0; -one;
Density (n. Y.) \u003d 0.0000899 g / cm 3;
Molar volume \u003d 14.1 cm 3 / mol.

Binary compounds of hydrogen with oxygen:

Hydrogen ("referring water") was opened by the English scientist. Cavendish in 1766. This is the easiest element in nature - a hydrogen atom has a kernel and one electron, probably, for this reason, hydrogen is the most common element in the universe (it is more than half the mass of most stars).

We can say about hydrogen that "a small spool, yes roads." Despite its "simplicity", hydrogen gives energy to all living beings on Earth - a continuous thermonuclear reaction is underway in the Sun during which one atom of helium is formed from four hydrogen atoms, this process is accompanied by the release of a colossal amount of energy (see nuclear synthesis).

In the earth's crust, the mass fraction of hydrogen is only 0.15%. Meanwhile, the overwhelming number (95%) of all chemicals known on Earth contain one or more hydrogen atoms.

In connections with non-metals (HCl, H 2 O, CH 4 ...), hydrogen gives its own only electron electronegative elements, showing the degree of oxidation +1 (more often), forming only covalent bonds (see covalent bond).

In compounds with metals (NAH, CAH 2 ...) hydrogen, on the contrary, takes on its only S-orbital another electron, thus trying to complete its electronic layer, showing the degree of oxidation -1 (less often), forming more often ion Communication (see ion connection), because, the difference in the electronegativity of the hydrogen atom and the metal atom can be quite large.

H 2.

In a gaseous state, hydrogen is in the form of two-heed molecules, forming a non-polar covalent bond.

Hydrogen molecules possess:

big mobility;
great strength;
low polarizability;
small sizes and mass.

Hydrogen gas properties:

the easiest gas in nature, without color and smell;
poorly dissolved in water and organic solvents;
in minor counts, dissolves in liquid and solid metals (especially in platinum and palladium);
it is difficult to liquefy (due to their small polarizability);
has the highest thermal conductivity of all known gases;
when heated, reacts with many non-metals, showing the properties of the reducing agent;
at room temperature reacts with fluorine (explosion occurs): H 2 + F 2 \u003d 2HF;
with metals reacts to the formation of hydrides, showing oxidative properties: H 2 + Ca \u003d Cah 2;

In compounds, hydrogen exhibits its rehabilitation properties much more than oxidative. Hydrogen is the strongest reducing agent after coal, aluminum and calcium. The reducing properties of hydrogen are widely used in industry to produce metals and non-metals (simple substances) from oxides and gallium.

Fe 2 O 3 + 3H 2 \u003d 2FE + 3H 2 O

Hydrogen reactions with simple substances

Hydrogen takes an electron by playing a role restorator, reactions:

from oxygen (in the ignition or in the presence of a catalyst), in the ratio 2: 1 (hydrogen: oxygen) is formed explosive Harmony gas: 2H 2 0 + O 2 \u003d 2H 2 +1 O + 572 kJ
from gray (When heated to 150 ° C-300 ° C): H 2 0 + S ↔ H 2 +1 S
from chlorom (when igniting or irradiation of UV rays): H 2 0 + Cl 2 \u003d 2H +1 Cl
from fluorine: H 2 0 + F 2 \u003d 2H +1 F
from nitrogen (When heated in the presence of catalysts or at high pressure): 3H 2 0 + N 2 ↔ 2NH 3 +1

Hydrogen gives an electron, playing a role oxidizer, in reactions with alkaline and alkaline earth Metals with the formation of metal hydrides - saline ion compounds containing hydride ions H - are unstable crystalline in-to-wa.

Ca + H 2 \u003d CAH 2 -1 2NA + H 2 0 \u003d 2NAH -1

For hydrogen, it is uncharacteristic to show the degree of oxidation -1. Reacting with water, hydrides decompose, restoring water to hydrogen. Calcium hydride reaction with water is as follows:

CAH 2 -1 + 2H 2 +1 0 \u003d 2H 2 0 + CA (OH) 2

Hydrogen reactions with complex substances

at high temperatures, hydrogen restores many metal oxides: Zno + H 2 \u003d Zn + H 2 O
methyl alcohol is obtained as a result of hydrogen reaction with carbon oxide (II): 2H 2 + Co → CH 3 OH
in hydrogenation reactions, hydrogen reacts with many organic substances.

In more detail, the equation of chemical reactions of hydrogen and its compounds are considered on the page "Hydrogen and its compounds - the equations of chemical reactions involving hydrogen".

The use of hydrogen

in nuclear power, hydrogen isotopes are used - deuterium and tritium;
in the chemical industry, hydrogen is used to synthesize many organic substances, ammonia, chloride;
in the food industry, hydrogen is used in the production of solid fats through hydrogenation of vegetable oils;
for welding and cutting of metals, a high temperature of hydrogen burning in oxygen (2600 ° C) is used;
when obtaining some metals, hydrogen is used as a reducing agent (see above);
since hydrogen is light gas, it is used in aeronautics as a filler of balloons, balloons, airship;
as the hydrogen fuel is used in the mixture with CO.

Recently, scientists pay a lot of attention to the search for alternative renewable energy sources. One of the promising areas is the "hydrogen" energy in which hydrogen is used as fuel, whose combustion product is ordinary water.

Methods for producing hydrogen

Industrial methods for producing hydrogen:

methane conversion (catalytic reduction of water vapor) water vapor at high temperature (800 ° C) on a nickel catalyst: CH 4 + 2H 2 O \u003d 4H 2 + CO 2;
the conversion of carbon oxide with water vapor (T \u003d 500 ° C) on the FE 2 O 3 catalyst: CO + H 2 O \u003d CO 2 + H 2;
thermal decomposition of methane: CH 4 \u003d C + 2H 2;
gasification of solid fuels (t \u003d 1000 ° C): C + H 2 O \u003d CO + H 2;
electrolysis of water (a very expensive method in which very pure hydrogen is obtained): 2H 2 O → 2H 2 + O 2.

Laboratory methods for producing hydrogen:

action on metals (more often zinc) hydrochloric or diluted with sulfuric acid: zn + 2hcl \u003d ZCl 2 + H 2; Zn + H 2 SO 4 \u003d ZNSO 4 + H 2;
the interaction of water vapor with hot iron chips: 4H 2 O + 3Fe \u003d Fe 3 O 4 + 4H 2.