Man, just like any other creature, cannot live without anions. In the meantime, do you know what an "anion" is?

AT normal conditions air molecules and atoms are neutral. However, when ionized, which can occur through ordinary radiation, ultraviolet radiation, microwave radiation, or through a simple lightning strike, air molecules lose part of their revolving around atomic nucleus negatively charged electrons, which later join neutral molecules, giving them negative charge. We call such molecules anions. Anions have no color or smell, and the presence of negative electrons in orbit allows them to attract various microsubstances from the air. Anions also remove dust from the air and kill germs.

The anion-air bond is analogous to the vitamin-food bond. That is why anions are also called "air vitamins", "element of longevity" and "air purifier". Although beneficial features anions remained long time in the shade, they are extremely important for human health. We cannot afford to neglect their healing properties.

So, anions can accumulate and neutralize dust, destroy viruses with positively charged electrons, penetrate into microbial cells and destroy them, thus preventing Negative consequences for human body. The more anions in the air, the less microbes in it (when the concentration of anions reaches a certain level, the content of microbes is completely reduced to zero). The content of anions in 1 cubic centimeter of air is as follows: 40-50 anions in residential areas of the city, 100-200 anions in urban air, 700-1000 anions in an open field and more than 5000 anions in mountain valleys and hollows. Human health directly depends on the content of anions in the air. If in falling in human body In the air, the content of anions is too low or, conversely, too high, then the person begins to breathe spasmodically, may feel tired, dizzy, have a headache, or even become depressed. All this can be treated, provided that the content of anions in the air entering the lungs is 1200 anions per 1 cubic centimeter. If the content of anions inside living quarters is increased to 1500 anions per 1 cubic centimeter, then your health will immediately improve; You will start working with redoubled energy, thereby increasing productivity. Thus, anions is an indispensable assistant in strengthening human health and prolonging life.

The International Health Organization has established that the minimum content of anions in fresh air is 1000 anions per 1 cubic centimeter. Under certain condition conditions environment(for example, in mountainous areas) people may never experience inflammation in their entire lives internal organs. As a rule, such people live long and remain healthy all their lives, which is the result of a sufficient content of anions in the air.

Negative ions are vital for human health and longevity.

For example, +, as well as in crystal lattices of compounds with ionic bond, for example, in common salt crystals, in ionic liquids and in melts of many inorganic substances.

acid residue

An anion in a complex inorganic compound is called an acid residue. It can be isolated in the formulas of inorganic acids and salts (Na 2 SO 4 , H NO 3 ); in them it is written in second place (after the cation). hallmark acid residue from other anions is that for almost all acid residues there is a corresponding acid: for example, SO 4 2– - "residue" of sulfuric acid, Cl- - of hydrochloric acid . Many acids exist only in solution, such as carbonic acid, but its salts (carbonates) are known. Some acids do not even exist in solutions; formally, salts of non-existent acids are attributed to them. However, they can form stable salts, for example with anions such as the phosphide ion ( P 3–). However, we repeat, they cannot be called acidic residues, since the acids corresponding to them do not exist, or they exist, but they are not chemically acids.

Inorganic acids and their corresponding acid residues

Acid	Name of the acid	acid residue	The name of the salts
H3BO3	ortho boric	BO 3 3-	ortho borate
H2CO3	coal	CO 3 2-	carbonate
H2SiO3	metasilicon	SiO 3 2-	metasilicate
H4SiO4	ortho silicon	SiO 4 4-	ortho silicate
HN 3	hydrazoic	N 3 -	azide
HNO 2	nitrogenous	NO 2 -	nitrite
HNO3	nitric	NO 3 -	nitrate
HPO 3	metaphosphoric	PO 3 -	metaphosphate
H3PO4	orthophosphoric	PO 4 3-	ortho phosphate
H3PO2	phosphorous	PO 2 3-	hypophosphite
H3PO3	phosphorous	PO 3 3-	phosphite
HAso 3	metaarsenic	AsO 3 -	metaarsenate
H 3 AsO 4	ortho arsenic	AsO 4 3-	ortho arsenate
H 2 S	hydrogen sulfide	S2-	sulfide
H2SO3	sulphurous	SO 3 2-	sulfite
H2SO4	sulfuric	SO 4 2-	sulfate
H 2 Se	hydroselenic	Se 2-	selenide
H 2 SeO 3	selenium	SeO 3 2-	selenite
H 2 SeO 4	selenic	SeO 4 2-	selenate
H 2 Te	telluric	Te 2-	telluride
H2TeO3	telluric	TeO 3 2-	tellurite
HF	hydrofluoric	F-	fluoride
HCl	hydrochloric	Cl-	chloride
HClO	hypochlorous	ClO-	hypochlorite
HClO 2	chloride	ClO 2 -	chlorite
HClO 3	chlorine	ClO 3 -	chlorate
HClO 4	chloride	ClO 4 -	perchlorate
HBr	hydrobromic	br-	bromide
HBrO	bromous	BrO-	hypobromite
HBrO2	bromide	BrO 2 -	bromite
HBrO 3	bromine	BrO 3 -	bromate
HBrO4	bromine	BrO4 -	perbromate
HI	hydroiodic	I-	iodide
HIO	iodine	IO-	hypoiodite
HIO 2	iodine	IO2 -	iodite
HIO 3	iodine	IO3-	iodate
HIO 4	iodine	IO 4 -	periodat

• The prefix "ortho" may be omitted, but this is not desirable.

see also

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Notes

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• // Encyclopedic Dictionary of Brockhaus and Efron: in 86 volumes (82 volumes and 4 additional). - St. Petersburg. , 1890-1907.

An excerpt characterizing Anion

On leaving Moscow, Petya, leaving his relatives, joined his regiment and soon after that was taken as an orderly to the general who commanded a large detachment. From the time of his promotion to the officers, and especially from his admission to active army, where he participated in the battle of Vyazemsky, Petya was constantly happily excited state joy that he is big, and in constant enthusiastic haste not to miss any case of real heroism. He was very happy with what he saw and experienced in the army, but at the same time it seemed to him that where he was not there, the most real, heroic things were now happening. And he was in a hurry to catch up to where he was not.
When on October 21 his general expressed a desire to send someone to Denisov's detachment, Petya so pitifully asked to be sent that the general could not refuse. But, sending him, the general, remembering Petya's insane act in the battle of Vyazemsky, where Petya, instead of going by road to where he was sent, rode into the chain under the fire of the French and fired two shots from his pistol there - sending him, the general he specifically forbade Petya to participate in any of Denisov's actions. From this, Petya blushed and became confused when Denisov asked if he could stay. Before leaving for the edge of the forest, Petya thought that he must, strictly fulfilling his duty, immediately return. But when he saw the French, saw Tikhon, learned that they would certainly attack at night, he, with the speed of young people moving from one look to another, decided with himself that his general, whom he still respected very much, was rubbish, German, that Denisov is a hero, and the esaul is a hero, and that Tikhon is a hero, and that he would be ashamed to leave them in difficult times.
It was already getting dark when Denisov, Petya and the esaul drove up to the guardhouse. In the semi-darkness one could see horses in saddles, Cossacks, hussars, adjusting huts in a clearing and (so that the French would not see the smoke) making a reddening fire in a forest ravine. In the hallway of a small hut, a Cossack, rolling up his sleeves, was chopping lamb. In the hut itself there were three officers from Denisov's party, setting up a table out of the door. Petya took off his wet clothes to dry and immediately began to assist the officers in setting up the dining table.
Ten minutes later, the table was ready, covered with a napkin. There was vodka on the table, rum in a flask, white bread and roast lamb with salt.
Sitting at the table with the officers and tearing up fat fragrant mutton with his hands, over which lard flowed, Petya was in an enthusiastic childish state. tender love to all people and, as a result, confidence in the same love for yourself of other people.
“So what do you think, Vasily Fyodorovich,” he turned to Denisov, “it’s all right that I’ll stay with you for a day?” - And, without waiting for an answer, he answered himself: - After all, I was ordered to find out, well, I will find out ... Only you will let me into the very ... into the main one. I don't need awards... But I want... - Petya clenched his teeth and looked around, twitching his head up and waving his arm.
- In the most important ... - repeated Denisov, smiling.
“Only, please, give me a command at all, so that I command,” Petya continued, “well, what is it worth to you? Oh, do you have a knife? - he turned to the officer who wanted to cut off the mutton. And he handed over his folding knife.
The officer praised the knife.
- Take it, please. I have a lot of them…” Petya said, blushing. - Fathers! I completely forgot,” he suddenly exclaimed. - I have wonderful raisins, you know, like this, without stones. We have a new marketer - and such wonderful things. I bought ten pounds. I'm used to anything sweet. Do you want? .. - And Petya ran into the hall to his Cossack, brought sacks, in which there were five pounds of raisins. Eat, gentlemen, eat.
- Do you need a coffee pot? he turned to the esaul. - I bought from our marketer, wonderful! He has wonderful things. And he is very honest. This is the main thing. I will definitely send you. And maybe also, flints have come out of yours, they have been trimmed - after all, this happens. I took with me, I have here ... - he pointed to the sacks - a hundred flints. I bought very cheap. Take, please, as much as you need, or that's all ... - And suddenly, frightened that he was lying, Petya stopped and blushed.
He began to remember if he had done any other stupid things. And, sorting through the memories of the present day, the memory of the French drummer presented itself to him. “It’s great for us, but what about him? Where do you share it? Did they feed him? Didn't you offend?" he thought. But having noticed that he had lied about the flints, he was now afraid.
“You could ask,” he thought, “but they will say: the boy himself took pity on the boy. I'll show them tomorrow what a boy I am! Will you be embarrassed if I ask? thought Petya. “Well, it doesn’t matter!” - and immediately, blushing and looking frightened at the officers, whether there would be mockery in their faces, he said:
- Can I call this boy that was taken prisoner? give him something to eat…maybe…
“Yes, miserable boy,” said Denisov, apparently not finding anything to be ashamed of in this reminder. - Call him here. Vincent Bosse is his name. Call.
"I'll call," said Petya.
- Call, call. Pitiful boy, - repeated Denisov.
Petya was standing at the door when Denisov said this. Petya crawled between the officers and came close to Denisov.
“Let me kiss you, my dear,” he said. - Oh, how wonderful! how good! - And, kissing Denisov, he ran into the yard.
- Bosses! Vincent! Petya shouted, stopping at the door.
- Who do you want, sir? said a voice from the darkness. Petya answered that the boy was a Frenchman, who was taken today.

Chemistry is a "magic" science. Where else can you get a safe substance by combining two dangerous ones? It's about about ordinary table salt - NaCl. Let us consider each element in more detail, based on previously obtained knowledge about the structure of the atom.

Sodium - Na, alkali metal (group IA).
Electronic configuration: 1s 2 2s 2 2p 6 3s 1

As you can see, sodium has one valence electron, which it "agrees" to donate in order for its energy levels to become complete.

Chlorine - Cl, halogen (group VIIA).
Electronic configuration: 1s 2 2s 2 2p 6 3s 2 3p 5

As you can see, chlorine has 7 valence electrons and he "lacks" one electron to complete his energy levels.

Now guess why the atoms of chlorine and sodium are so "friendly"?

Earlier it was said that inert gases (group VIIIA) have completely "staffed" energy levels - they have completely filled outer s and p-orbitals. From here they so badly enter into chemical reactions with other elements (they simply do not need to be "friends" with anyone, since they "don't want to" give or receive electrons).

When valence energy level filled - the element becomes stable or rich.

Inert gases are "lucky", but what about the rest of the elements periodic table? Of course, "searching" for a mate is like a door lock and a key - a certain lock has its own key. So and chemical elements, trying to fill their external energy level, enter into reactions with other elements, creating stable compounds. Because the outer s (2 electrons) and p (6 electrons) orbitals are filled, then this process is called "octet rule"(octet = 8)

Sodium: Na

There is one electron in the outer energy level of the sodium atom. To go to a stable state, sodium must either donate this electron or accept seven new ones. Based on the foregoing, sodium will donate an electron. In this case, the 3s-orbital "disappears" in it, and the number of protons (11) will be one greater than the number of electrons (10). So, neutral atom sodium will turn into a positively charged ion - cation.

Electronic configuration of the sodium cation: Na+ 1s 2 2s 2 2p 6

Particularly attentive readers will rightly say that neon (Ne) has the same electronic configuration. So what, sodium turned into neon? Not at all - don't forget protons! Them still; sodium has 11; neon has 10. It is said that the sodium cation is isoelectronic neon (because electronic configurations are the same).

Summarize:

• the sodium atom and its cation differ by one electron;
• the sodium cation is smaller because it loses its external energy level.

Chlorine: Cl

In chlorine, the situation is exactly the opposite - it has seven valence electrons at the external energy level and it needs to accept one electron in order to become stable. In this case, the following processes will take place:

• the chlorine atom will accept one electron and become negatively charged anion(17 protons and 18 electrons);
• electron configuration of chlorine: Cl- 1s 2 2s 2 2p 6 3s 2 3p 6
• the chloride anion is isoelectronic to argon (Ar);
• since the external energy level of chlorine is "finished", the radius of the chlorine cation will be slightly larger than that of the "pure" chlorine atom.

Table salt (sodium chloride): NaCl

Based on the above, it is clear that the electron that gives up sodium becomes the electron that receives chlorine.

AT crystal lattice sodium chloride, each sodium cation is surrounded by six chloride anions. Conversely, each chloride anion is surrounded by six sodium cations.

As a result of the movement of an electron, ions are formed: sodium cation(Na+) and chloride anion(Cl-). Since opposite charges attract, there is stable connection NaCl (sodium chloride) - table salt.

As a result of mutual attraction of oppositely charged ions, formed ionic bond- stable chemical compound.

Compounds with ionic bonds are called salts. Everything in solid state ionic compounds are crystalline.

It should be understood that the concept of an ionic bond is rather relative, strictly speaking, only those substances in which the difference in the electronegativity of the atoms that form an ionic bond can be attributed to "pure" ionic compounds is equal to or more than 3. For this reason, in nature there are only a dozen purely ionic compounds are fluorides of alkali and alkaline earth metals (for example, LiF; relative electronegativity Li=1; F=4).

In order not to "offend" ionic compounds, chemists agreed to consider that chemical bond is ionic if the difference in the electronegativity of the atoms that form the molecule of a substance is equal to or greater than 2. (see the concept of electronegativity).

Cations and anions

Other salts are formed in the same way as sodium chloride. The metal donates electrons and the non-metal receives them. It can be seen from the periodic table that:

• elements of group IA ( alkali metals) donate one electron and form a cation with a charge of 1 + ;
• group IIA elements ( alkaline earth metals) donate two electrons and form a cation with a charge of 2 + ;
• elements of group IIIA donate three electrons and form a cation with a charge of 3 + ;
• elements of group VIIA (halogens) accept one electron and form an anion with a charge of 1 - ;
• elements of the VIA group accept two electrons and form an anion with a charge of 2 - ;
• elements of the VA group accept three electrons and form an anion with a charge of 3 - ;

Common monatomic cations

Common monatomic anions

Not everything is so simple with transition metals (group B), which can give different amount electrons, thus forming two (or more) cations with different charges. For example:

• Cr 2+ - divalent chromium ion; chromium(II)
• Mn 3+ - trivalent manganese ion; manganese(III)
• Hg 2 2+ - ion of diatomic divalent mercury; mercury(I)
• Pb 4+ - tetravalent lead ion; lead(IV)

many ions transition metals can have varying degrees oxidation.

Ions are not always monatomic, they can consist of a group of atoms - polyatomic ions. For example, the ion of diatomic divalent mercury Hg 2 2+: two mercury atoms are bound into one ion and have a total charge of 2 + (each cation has a charge of 1 +).

Examples of polyatomic ions:

• SO 4 2- - sulfate
• SO 3 2- - sulfite
• NO 3 - - nitrate
• NO 2 - - nitrite
• NH 4 + - ammonium
• PO 4 3+ - phosphate

Anions are components of double, combined, medium, acidic, basic salts. In qualitative analysis, each of them can be determined using a specific reagent. Let us consider qualitative reactions to anions used in inorganic chemistry.

Analysis Features

It is one of the most important options for identifying substances common in inorganic chemistry. There is a division of analysis into two components: qualitative, quantitative.

All qualitative reactions to anions imply the identification of a substance, the establishment of the presence of certain impurities in it.

Quantitative analysis establishes a clear content of impurities and the base substance.

Specifics of Qualitative Detection of Anions

Not all interactions can be used in qualitative analysis. A reaction is considered characteristic, which leads to a change in the color of the solution, the precipitation of a precipitate, its dissolution, and the release of a gaseous substance.

The anion groups are determined by a selective reaction, due to which only certain anions can be detected in the composition of the mixture.

Sensitivity is the lowest concentration of a solution at which the anion to be determined can be detected without pretreatment.

Group reactions

There are such chemical substances, which are capable of giving similar results when interacting with different anions. Thanks to the use of a group reagent, it is possible to isolate various groups anions by precipitating them.

When conducting chemical analysis inorganic substances, mainly, they study aqueous solutions in which salts are present in a dissociated form.

That is why the anions of salts are determined by their discovery in a solution of a substance.

Analytical groups

In the acid-base method, it is customary to distinguish three analytical groups of anions.

Let us analyze which anions can be determined using certain reagents.

sulfates

For their detection in a mixture of salts in a qualitative analysis, soluble barium salts are used. Considering that sulfate anions are SO4, the short ionic equation for the ongoing reaction is:

Ba 2 + + (SO 4) 2- \u003d BaSO4

The barium sulfate obtained as a result of the interaction has White color, is an insoluble substance.

Halides

When determining chlorine anions in salts, soluble silver salts are used as a reagent, since it is the cation of this noble metal gives an insoluble white precipitate, so chloride anions are defined this way. This is not a complete list of qualitative interactions used in analytical chemistry.

In addition to chlorides, silver salts are also used to detect the presence of iodides and bromides in a mixture. Each of the silver salts that form a compound with a halide has a specific color.

For example, AgI is yellow.

Qualitative reactions to anions of the 1st analytical group

Let us first consider which anions it contains. These are carbonates, sulfates, phosphates.

The most common in analytical chemistry is the reaction for the determination of sulfate ions.

For its implementation, you can use solutions of potassium sulfate, barium chloride. When these compounds are mixed together, a white precipitate of barium sulfate is formed.

In analytical chemistry prerequisite is the writing of molecular and ionic equations of those processes that were carried out to identify the anions of a certain group.

If we write the full and reduced ionic equation for this process, the formation of the insoluble salt BaSO4 (barium sulfate) can be confirmed.

When a carbonate ion is detected in a mixture of salts, a qualitative reaction is used with inorganic acids, accompanied by the release of a gaseous compound - carbon dioxide. In addition, when detecting carbonate in analytical chemistry, the reaction with barium chloride is also used. As a result of ion exchange, a white precipitate of barium carbonate precipitates.

The reduced ionic equation of the process is described by the scheme.

Barium chloride precipitates carbonate ions as a white precipitate, which is used in the qualitative analysis of anions in the first analytical group. Other cations do not give such a result, therefore they are not suitable for determination.

When carbonate reacts with acids, a brief ionic equation has the following form:

2H + +CO 3 - \u003d CO 2 +H 2 O

When detecting phosphate ions in a mixture, it is also used soluble salt barium. Mixing a sodium phosphate solution with barium chloride results in the formation of insoluble barium phosphate.

Thus, we can conclude that barium chloride is universal and can be used to determine anions of the first analytical group.

Qualitative reactions to anions of the second analytical group

Chloride anions can be detected by interaction with a solution of silver nitrate. As a result of ion exchange, a cheesy white precipitate of silver chloride (1) is formed.

The bromide of this metal has a yellowish color, and the iodide has a rich yellow color.

The molecular interaction of sodium chloride with silver nitrate is as follows:

NaCl + AgNO 3 \u003d AgCl + NaNO 3

Among the specific reagents that can be used in the determination of iodide ions in a mixture, we single out copper cations.

KI + CuSO 4 \u003d I 2 + K 2 SO 4 + CuI

This redox process is characterized by the formation of free iodine, which is used in qualitative analysis.

silicate ions

To detect these ions, concentrated mineral acids are used. For example, when added to sodium silicate concentrated of hydrochloric acid a precipitate of silicic acid is formed, which has a gel-like appearance.

In molecular form, this process:

Na 2 SiO 3 + 2HCl \u003d NaCl + H 2 SiO 3

Hydrolysis

In analytical chemistry, anion hydrolysis is one of the methods for determining the reaction of a medium in salt solutions. In order to correctly determine the variant of the ongoing hydrolysis, it is necessary to find out from which acid and base the salt was obtained.

For example, aluminum sulfide is formed by insoluble aluminum hydroxide and weak hydrosulfide acid. AT aqueous solution This salt is hydrolyzed by the anion and by the cation, so the medium is neutral. None of the indicators will change its color, therefore, it will be difficult to determine the composition of this compound by hydrolysis.

Conclusion

Qualitative reactions, which are used in analytical chemistry to determine anions, make it possible to obtain certain salts in the form of precipitation. Depending on the anions of which analytical group it is necessary to identify, a certain group reagent is selected for the experiment.

This is the method used to determine the quality drinking water, revealing whether the quantitative content of anions of chlorine, sulfate, carbonate does not exceed those maximum permissible concentrations that are established by sanitary and hygienic requirements.

In conditions school laboratory experiments related to the determination of anions are one of the options for tasks research character on the practical work. During the experiment, schoolchildren not only analyze the colors of the resulting precipitation, but also draw up reaction equations.

In addition, the elements qualitative analysis offered to graduates final tests in chemistry, allow you to determine the level of knowledge of future chemists and engineers in molecular, complete and reduced ionic equations.

ANIONS (negative ions) What are anions? How do anions affect the human body?

What are anions?

Molecules and atoms of air, under normal conditions, are neutral. But with the ionization of air, which can happen through ordinary radiation, microwave radiation, ultraviolet radiation, sometimes simply through a simple lightning strike. The air is discharged - oxygen molecules lose some of the negatively charged electrons revolving around the atomic nucleus, which later find and join any neutral molecules, giving them a negative charge. Such negatively charged molecules are called anions. Man cannot exist without anions, like any other living being.

The aroma of fresh air - we feel the presence of anions in the air of wildlife: high in the mountains, by the sea, immediately after rain - at this time we want to breathe deeply, inhale this purity and freshness of the air. Anions (negatively charged ions) of the air are called air vitamins. Anions treat diseases of the bronchi, the human pulmonary system, are a powerful means of preventing any disease, increase the immunity of the human body. Negative ions (Anions) help purify the air from bacteria, microbes, pathogenic microflora and dust, bringing the number of bacteria and dust particles to a minimum, and sometimes to zero. Anions have a good long-term cleansing and disinfecting effect on the microflora of the surrounding air.

Human health directly depends on the quantitative content of anions in the ambient air. If there are too few anions in the surrounding space in the air that enters the human body, then the person begins to breathe spasmodically, may feel tired, begin to feel dizzy and have a headache, or even become depressed. All these conditions are treatable if the anion content in the air entering the lungs is at least 1200 anions per 1 cubic centimeter. If you increase the content of anions inside residential premises to 1500-1600 anions per 1 cubic centimeter, then the well-being of people living or working there will improve dramatically; You will begin to feel very good, work with redoubled energy, thereby increasing your productivity and the quality of work.

With direct contact of anions with the skin, due to the high penetrating ability of negative ions, complex reactions occur in the human body. biochemical reactions and processes that contribute to:

general strengthening of the human body, immunity and maintaining the energy status of the body as a whole

improvement of blood supply to all organs, improvement brain activity, prevention of oxygen deficiency of the brain,

Anions improve the functioning of the heart muscle, kidney and liver tissues

anions enhance blood microcirculation in the vessels, increase tissue elasticity

negatively charged particles (anions) prevent aging of the body

anions contribute to the activation of anti-edematous and immunomodulatory effects

anions help against cancer, tumors, increase the body's own antitumor defenses

with an increase in anions in the air, the conductivity of nerve impulses improves

Thus follows:

Anions (negative ions) are an indispensable assistant in strengthening human health and prolonging his life